Microcomputer Sensing Control System

Microcomputer Sensing Control System
KL-620 Microcomputer Sensing Control System Training Course

Main Unit General Sensors (I) Temp I (AD590) Humidity CDS Photovoltaic
Unit 0 : KL-62001 General Sensors (I) Unit 1 : KL-64001 Temp I (AD590) Humidity Unit 5 : KL-64005 CDS Photovoltaic Unit 9 : KL-64009 Level (Water) Unit 13 : KL-64013 General Sensors (II) Unit 2 : KL-64002 Infrared Ultrasonic Unit 6 : KL-64006 V/F Converter Unit 10 : KL-64010 Fiber Optic Unit 14 : KL-64014 General Sensors (III) Unit 3 : KL-64003 Pressure Strain Gauge Unit 7 : KL-64007 F/V Converter Unit 11 : KL-64011 LVDT Unit 15 : KL-64015 Gas/Smoke Ethanol Unit 4 : KL-64004 Hall Current Proximity Unit 8 : KL-64008 Temp II (PT100) Unit 12 : KL-64012 Rotation Angle Unit 16 : KL-64016

Unit 0 : KL-62001 Main Unit In this Unit, the operation of each block on Main Unit will be introduced. After study complete, users are able to use KL as measurement and assist tool for KL-620 experiments. 1. System Test 6. Alarm Amplifier Test 2. DCV Measurement (Manual) 7. Comparator Test 3. DCV Measurement (Chip) 8. Differential Amplifier Test 4. DCV Measurement (PC) 9. Instrumentation Amplifier 5. D/A Converter Test 10. Other MCU Function Test Menu

System Test Objective: Blocks to be demonstrated:
To understand how to self test Single Chip and EPROM. Blocks to be demonstrated: Thumbwheel Switch Status Display Single Chip Out Control 2 Out Control 3 EPROM Back

Procedure: Turn off the power. Connect the wires as shown in next slide. Turn on the power.  If the speaker beep 4 times and the Status Display shows “1”, it means that the Single Chip and EPROM work functionally. Remove Control2 from Ground.  The Status Display will display the value shown on Thumbwheel Switch. Adjust the Thumbwheel Switch below  The Status Display will show the current value of the Thumbwheel Switch. Adjust the Thumbwheel Switch over 4095  The speaker will alarm and the Status Display shows “0000”.

Control2  GND Control3  GND

DCV Measurement (Manual)
Objective: To understand how to use Potentiometer. To use DC Voltage Meter to measure DC Voltage manually. Blocks to be demonstrated: DC Power +12V, -12V Status Display MODE Button Range Button Select / Manual Potentiometer Back

Procedure: Discussion: Turn off the power.
Connect the wires as shown in next slide. Turn on the power. Press Range button twice.  Select the measuring range of DCV ( -20V ~ +20V) Rotate the Potentiometer.  The output voltage at VR2 will display at Status Display section (-12V ~ +12V) . Discussion: When connects MANUAL to the GND, Status Display Section acts as DC Voltage Meter.

Connect to GND +12V  VR3 +Input  VR2 Manual  GND -12V  VR1

DCV Measurement (Chip)
Objective: Use A/D Converter, Single Chip and Status Display to measure DC voltage Blocks to be demonstrated: DC Power +5V, GND Status Display MODE Button Range Button A/D Converter Select / Chip Potentiometer Back

Connect the wires as shown in next slide. Turn on the power. Press Range button twice.  Select the measuring range of DCV ( -20V ~ +20V) Rotate the Potentiometer.  The output voltage at VR2 will display at Status Display section (0V ~ +5V) . Discussion: Warning!! The max voltage input to ADC is 5V. When connecting CHIP to the GND, the analog signal received from A/D Converter will send to single chip for decoding and output to 7 segment display. When sending the analog signal to the PC, the signal should be converted to digital format. As the result, this technique will be used when connecting the main unit to the PC. Check next exercise.

+5V  VR1 A/D IN  VR2 GND  VR1 Chip  GND

DCV Measurement (PC) Objective: Blocks to be demonstrated:
Use computer interface to acquire and record DC voltage Blocks to be demonstrated: DC Power +5V, GND RS-232C A/D Converter Select / Chip Potentiometer Back

Procedure: Discussion:
Turn off the power and connect the wires as shown in next slide. Connects RS-232C port to PC COM port by using K&H RS-232 Cable. Turn on the power and launch the KL-620 software. Press the [Acquire] button.  Start to record the DC voltage. Rotate the Potentiometer.  The output voltage at VR2 will display at software panel. Warning!! The max voltage swing input to ADC is -5V ~ +5V. Discussion: When connecting CHIP to the GND and CTRL pin to GND, the analog signal received from A/D Converter will send to PC through RS-232 interface.

Connect to PC COM1 +5V  VR3 CTRL  GND A/D IN  VR2 GND  VR1
Chip  GND

KL-620 Software Interface for Data Acquisition
Load saved data Graphic and Cursor control panel Save data in Excel format Data stored in Table Press acquire button to start acquire data Setup trigger level for background color Change Y-axis Name and Scale Setup Acquire Frequency, Number and Gain Current, Min, and Max value

D/A Converter Test Objective: Blocks to be demonstrated:
Use DCV to measure the voltage converted from D/A Converter Blocks to be demonstrated: Thumbwheel Switch Status Display D/A Converter Select / Manual Back

Turn off the power and connect the wires as shown in next slide. Turn on the power. Press Range button twice Setup DCV measuring range (-20V ~ +20V) Adjust Thumbwheel Switch below 4095, for example 3512  Status Display will show close to 3.512, meaning that the output voltage of DA Converter is Volt. Adjust Thumbwheel Switch above 4095  Status Display will show close to and speaker start beeping. Discussion: The digital output of thumbwheel switch (12-bit) is connected to 12-bit D/A Converter DA0~DA11 and convert to DC voltage. The scale for converting is 1 bit = 0.001V i.e. (0000~4095 => 0.000~4.095V)

+Input  OUT+ Connect to GND Manual  GND

Alarm Amplifier Test Objective: Blocks to be demonstrated:
Understand the connection and function of alarm amplifier block Blocks to be demonstrated: DC Power GND, +5V Alarm Amplifier Potentiometer Back

Turn off the power and connect the wires as shown in next slide. Turn on the power. Rotate the Potentiometer  When the applied voltage is higher than 0.7V, the buzzer will be ON. Discussion: The schematic of the Alarm Amplifier block is shown below. When the applying voltage to Signal Input of Alarm Amplifier is above around 0.7 volt, transistor will be ON and the buzzer will start alarming. Signal Input From Single Chip Buzzer

+5V  VR3 GND  VR1 SIN. IN  VR2

Comparator Test Objective: Blocks to be demonstrated:
Understand the connection and function of comparator block Blocks to be demonstrated: DC Power GND, +5V,+12V Comparator Select / Manual Potentiometer Back

Turn off the power and connect the wires as shown in next slide. Turn on the power. Press Range button twice (20V range) Rotate the Potentiometer  When V+ > V-, Vo outputs a positive 10 volt. When V- > V+, Vo outputs a negative 10 Volt. Discussion: The schematic of the Comparator is shown below. V- Vo V+

+12V  VR3 +5V  V- +Input  Vo Connect to GND GND  VR1 V+  VR2 Manual  GND

Differential Amplifier Test
Objective: Understand the connection and function of differential amplifier block. Blocks to be demonstrated: DC Power +12V, +5V,-5V Differential Amplifier Select / Manual Back

Turn off the power and connect the wires as shown in next slide. Turn on the power. Select Range button to 20V range  The Status Display shows 7 (Volt). Connects V+ to DC -5V and V- remains connecting to DC +5V  The Status Display shows -10 (Volt) Discussion: The output voltage of differential amplifier is equal to V+ - V-. However due to the power supplied limit of amplifier, the maximum difference is equal to 12 Volt. The schematic of the differential amplifier is shown and explained below. V- Vo V+ 10k 2 I

+12V  V+ +5V  V- +Input  Vo Connect to GND Manual  GND

Instrumentation Amplifier Test
Objective: Understand the connection and function of instrumentation amplifier block. Blocks to be demonstrated: Thumbwheel Switch Instrumentation Amplifier D/A Converter Select / Manual Potentiometer Back

Use multi-meter and adjust Potentiometer until the resistance between VR2 and VR3 is equal to 40k Ohm. Setup Thumbwheel Switch to be 0200  D/A Converter OUT+ = 0.2 Volt Connect wires as shown in next page. Turn on the power. Select Range button to 20V range  Status Display shows 1.2V Discussion: Vo VR R1:100k R2:10k R3:10k VR1 VR3 VR2 Vi- Vi+ The schematic of the instrumentation amplifier block is shown at right side, where = 6

OUT+  V- GND  V+ +Input  Vo VR1  VR1 Connect to GND VR3  VR3 VR2  VR2 Manual  GND

Other MCU Function Test
Objective: To understand the Out Control pin1 and pin4 of MCU block Blocks to be demonstrated: DC Power +5V, GND Thumbwheel Switch Status Display A/D Converter Single Chip Out Control 1 Out Control 4 Alarm Amplifier Select / Chip Potentiometer Back

Procedure: Turn off the power. Connect the wires as shown in next slide. Setup Thumbwheel Switch to be [1000]  Setup Alarm level equal to Volt. (See discussion below) Turn on the power. Select Range button to 20V range Adjust the Potentiometer so that the Status Display shows higher than (Volt)  Out Control 1 outputs a continuous pulse (pulse width = 0.5 sec) to the alarm amplifier and enable the alarm. Adjust the Potentiometer so that the Status Display shows lower than or equal to (Volt)  Out Control 1 outputs a LOW state, no sound outputs from alarm. Remove Out Control 1 from Alarm Amplifier SIN. IN Connect Out Control 4 to Alarm Amplifier SIN. IN Adjust the Potentiometer so that the Status Display shows higher than (Volt)  Out Control 4 outputs a LOW state. Adjust the Potentiometer so that the Status Display shows lower than or equal to (Volt)  Out Control 4 outputs a HIGH state and alarm amplifier starts alarming.

+5V  VR3 A/D IN  VR2 Out Control1  SIN. IN GND  VR1 Chip  GND

Scaling the Preset level from 0000 ~ 4095 to 0000~5000
Discussion: Scaling the Preset level from 0000 ~ 4095 to 0000~5000 Preset Level 0000~4095 Scaled Level 0000~5000 The range of the preset level is from 0000~4095. The range of the voltage level output from AD converter is from 0V~5V (0000~5000) As the result, when the preset level is set to 1000 and when the AD In voltage exceed 1221, the alarm beeps. (Outputs from Control 1). Another example, when the preset level is set to 3000 and when the AD In voltage exceed 3663, the alarm beeps. (Outputs from Control 1). 1000 2000 3000 4000 4095 = 0000 1221 2442 3663 4884 5000 = = = = = Formula : = x 5000 4095 Scaled Value Preset Level

Unit 1 : KL-64001 General Sensors (I) You have learned how to use Main Unit KL as a measurement and assist tool from previous Unit. In this Unit, 4 different types of common sensors are introduced. The connections of the modules to the Main Unit will not be introduced. Any questions regard to the Main Unit connections can be referred to Unit 0. 1. Photo Transistor 2. Photo Interrupter 3. Magnetic Hall Effect (Digital) 4. Magnetic Hall Effect (Analog) Menu

Photo Transistor Structure: Symbol: Window Wire C Chip E Lead wire
The electrons that are generated by photons in the base-collector junction are injected into the base, and this current is then amplified by the transistor operation. i.e., The light striking the base replaces what would ordinarily be voltage applied to the base – so, a phototransistor amplifies variations in the light striking it. Back

Circuit Explanation: Ic Iλ Photons  Iλ Ic Vo1 WHEN Photons  Iλ Ic

Experiment Procedure:
With power off, connect Vo1 to the Main Unit DCV INPUT+. Turn on the power. Cover the phototransistor with hand and record the output voltage Vo1? Lighten the phototransistor with fluorescent lamp and record the output voltage Vo1?  What is the relation between the output voltage and the distance between light source and phototransistor?  Note: If you don’t know how to use DCV, please check Unit 0 Answers: 3.  ~ 5 Volt 4.  0.1 V ~ 4.0 V, depends on the magnitude of the light source. 5.  The longer the distance, the higher output voltage

Photo Interrupter Structure: Symbol: Barrier Emitter + Detector E D
Lead wire Fixed hole D + E A common implementation involves an LED and a Phototransistor, separated so that light may travel across a barrier but electrical current may not. When an electrical signal is applied to the input of the photo interrupter, its LED lights, its light sensor then activates, and a corresponding electrical signal is generated at the output. Back

Circuit Explanation: Ic In normal situation:
Vo2’ In normal situation: Detector receives light signal from LED  Vo2’ = LOW  Vo2 = LOW When an object block the light bean: Collector current Ic decreases  Vo2’ = High  Vo2 = High The two inverters act as a wave shaper and Schmitt trigger Latch.

With power off, connect Vo2 to the SIN. IN of Alarm Amplifier of on Main Unit. Turn on the power. What’s the status of the alarm when nothing block the light bean? What’s the status of the alarm when an object blocks the light bean?  Use oscilloscope to compare the wave shape of Vo2’ and Vo2  Note: If you don’t know how to use DCV, please check Unit 0 Answers: 3.  nothing happened 4.  start alarming 5.  Vo2 Vo2’

Magnetic Hall Effect (Digital)
Structure: Symbol: Hall IC Output Supply Ground Pinning is shown from brand side The linear Hall-effect sensor detects the motion, position, or change in field strength of an electromagnet. The output null voltage is nominally one-half the supply voltage. A south magnetic pole, presented to the branded face of the Hall effect sensor will drive the output higher than the null voltage level. A north magnetic pole will drive the output below the null level. Back

Circuit Explanation: Vo3’ Magnet The voltage of Vo3’ is affected by the pole and magnitude of the magnetic field. When South pole approaches to the sensor  Vo3’ When North pole approaches to the sensor  Vo3’ The two inverters act as a wave shaper and Schmitt trigger Latch.

With power off, connect Vo3’ to DCV. Turn on the power. What’s the value of Vo3’ shown on DCV?  Move the magnet (North pole face to the device) toward the Hall IC and observe the value of Vo3’ shown on DCV. Move the magnet (South pole face to the device) toward the Hall IC and observe the value of Vo3’ shown on DCV. Replace the measure point from Vo3’ to Vo3, and repeat step 4  Replace the measure point from Vo3’ to Vo3, and repeat step 5  Answers: 3.  ~2.5 Volt 4.  2.5V ~ 4.1V, the closer the magnet, the higher output voltage.  2.5V ~ 1.1V, the closer the magnet, the lower the output voltage.  5 Volt  0 Volt

Magnetic Hall Effect (Analog)
Structure: Symbol: Hall Element Vin GND Vout1 Vout1 Vout2 Vin Vout2 GND The Hall element provides an output voltage that is proportional to the magnetic filed which it is exposed. The sensed magnetic field can be either positive or negative. As a result, the output of the amplifier will be driven either positive or negative Back

Circuit Explanation: Vout1 Vout2
Magnet The voltage of Vout1 and Vout2 is affected by the pole and magnitude of the magnetic field. When South pole approaches to the sensor  Vout1 Vout2  Vo4 When North pole approaches to the sensor  Vout1 Vout2  Vo4 Variable resistor R9 is used for offset adjustment.

With power off, connect Vo4 to DCV. Turn on the power. Adjust variable resistor R9 so that Vo4 is equal to 0 Volt. Move the magnet (North pole face to the device) toward the Hall IC and observe the value of Vo4 shown on DCV. Move the magnet (South pole face to the device) toward the Hall IC and observe the value of Vo4 shown on DCV. Answers: 4.  Vo4 = 0 ~ 6 Volt The closer the magnet, the higher output voltage (positive direction). 5.  Vo4 = 0 ~ -6 Volt The closer the magnet, the higher output voltage (negative direction).

General Sensors (II) Unit 2 : KL-64002 5. Pyroelectric Detector
6. Reed Switch 7. Thermistor 8. Mercury Switch Menu

Pyroelectric Detector
Symbol: Structure: D Filter Window Drain Source Gate G S The pyroelectric sensor is made of a crystalline material that generates a surface electric charge when exposed to heat in the form of infrared radiation. When the amount of radiation striking the crystal changes, the amount of charge also changes and can then be measured with a sensitive FET device built into the sensor. The sensor elements are sensitive to radiation over a wide range so a filter window is added to the package to limit incoming radiation to the 8 to 14μm range which is most sensitive to human body radiation. Back

Circuit Explanation: Vs
When human body towards to the sensor  a negative pulse signal should present at the source terminal of FET  U1 amplifies the pulse When human body away from the sensor  a positive pulse signal should present at the source terminal of FET  U1 amplifies the pulse Coupling Capacitor C1 blocks the DC signal from the sensor.

With power off, connect CH1 of the oscilloscope to Vo5. Set oscilloscope CH1 to AC coupling (500mV,500mS) Adjust variable resistor R5 to maximum (rotate the knob clockwise until reaching end position) Turn on the power. Weave your hand on the top of the sensor and observe the waveform shown on the oscilloscope  Toward your hand to the top of the sensor slowly, stay for 2 sec, and remove your hand away from the sensor slowly, check the waveform  Answers: 5.   Toward Away

Reed Switch Symbol: Structure: Reed Sealed glass Contact
The reed switch is a type of mechanical-contact switch. Two metal reeds are enclosed in a hermetically sealed glass capsule. A normally open (NO) reed switch is shown above. The overlapping reeds can be closed or opened by positioning a permanent magnet close to the reed contacts. Back

Circuit Explanation: When switch close  Q1 ON  Buzzing
When switch open  Q1 OFF  No Buzzer

Power On the module. Approach a magnet from the top of the sensor to the sensor contact (Magnetic field is in vertical with the contact plate). What is the status of the buzzer?  Approach a magnet from the side of the sensor to the sensor contact. (Magnetic field is in parallel with the contact plate). What is the status of the buzzer?  Answers: 2.  Buzzer is ON 3.  Buzzer is OFF

Thermistor Symbol: Structure: Epoxy Lead wire
Thermistors are temperature sensitive resistors. Increasing the temperature will decreases the resistance (in most cases). This type also called NTC type (Negative Temperature Coefficient). When used for temperature measurements, the current flowing through thermistors must be kept very low (typical less than 0.1 mA) to assure near-zero power dissipation and near-zero self heating. Back

Circuit Explanation: v1
When Temp.  RSENSOR  V  Q2 ON  Q3 ON  LED ON When Temp.  RSENSOR  V  Q2 OFF  Q3 OFF  LED OFF

With power off, connect DCV to Q2 base. Turn on the power, adjust variable resistor R8 until V1 equal to 0.95V. Rub the thermistor  Blow the thermistor  Answers: 3.  LED starts lighting up when V1 reach about 1 Volt. 4.  LED dims.

Mercury Switch Symbol: Structure: Glass Case Mercury
Two electrodes and mercury are enclosed in a hermetically sealed glass capsule. When the sensor tilted a angle about 15 degrees, two electrodes are closed by mercury. Back

Circuit Explanation: When switch short  Q4 ON  Buzzer ON
When switch open  Q4 OFF  Buzzer OFF

Power on the module. Tilt the sensor until the mercury reaching two electrodes. What is the status of the buzzer? Answers: 2.  Buzzer starts buzzing

General Sensors (III) Unit 3 : KL-64003 9. Limit Switch
10. Vibration Switch 11. Condenser Microphone 12. Dynamic Microphone Menu

Limit Switch Symbol: Structure: Actuator NO Normal open COM
Normal Close COM NC The limit switch uses physical contact to change state. Upon contact, when an object comes into contact with the actuator, the device operates the contacts to make or break an electrical connection. Back

Circuit Explanation: When not actuated :
1 = High ; 5 = Low  4 = High ; LED2 OFF  2 = High  3 = Low ; 6 = Low LED1 ON When actuated : 1 = Low ; 6 = Low  4 = Low ; 2 = Low  LED2 ON  3 = High ; 6 = High  LED1 OFF (from previous state)

Power on the module. Press the button to actuate the circuit, what’s the state of the LED?  Release the button, what’s the state of the LED?  Answers: 2.  LED1 OFF ; LED2 ON 3.  LED1 ON ; LED2 OFF

Vibration Switch Symbol: Structure: Housing Contact: to spring Contact
to metal The vibration switch is normally open with vibration springs. When a vibration occurred, the switch changes to close state and the switch turns ON. Back

Circuit Explanation: When vibration switch is OFF :
555 Timer (U2) OFF  no output at Vo10  Buzzer OFF When vibration switch is ON : 555 Timer (U2) ON  pulse output at Vo10  Buzzer ON

Power on the module. What is the status of the buzzer? Knock the sensor from side, what is the status of the buzzer? Knock the sensor from top, what is the status of the buzzer? Answers: 2.  Buzzer is OFF 3.  Buzzer is beeping. 4.  no response from the buzzer.

Condenser Microphone Symbol: Structure: VCC Audio Out GND Ground
Vcc / Audio Signal The condenser microphone is constructed with a pair of metal plates that move closer or further apart in response to air vibrations. One rigid plate is connected to ground, the other moving plate is flexible and positively charged by an external voltage. The Condenser microphone is good for crisp sound and can be used for high quality recordings. Back

Circuit Explanation: The output voltage of the microphone sends to COMMON SPEAKER AMPLIFIER block for signal amplification and driving the speaker.

Connects Vo11 (COMDENSER MICROPHONE block) to Vin1 (COMMON SPEAKER AMPLIFIER block). Power on the module. Input voice at the microphone, what happened to the speaker? (using variable resistor R11 to adjust the gain)  Blow the microphone and use oscilloscope to record the maximum amplitude of the waveform at Vo11. (note: this result will be used to compare to the result at next exercise. Answers: 3.  When rotate right R11, the volume is higher.  When rotate left R11, the volume is lower. 4.  Max amplitude = 3 Vpp.

Dynamic Microphone Symbol: Structure: Audio Out Ground Diaphram
Dynamic microphones contain a plastic membrane or diaphram. A metal coil inside is connected to the diaphram on one end and a magnet on the other When the diaphram moves in response to air vibrations the coil moves across the magnet creating a current throught induction. Back

Circuit Explanation: The dynamic microphone converts the sound waves to electric signal at Vo12.

Power on the module. Connects Vo12 (DYNAMIC MICROPHONE block) to oscilloscope. Blow the microphone and use oscilloscope to record the maximum amplitude of the waveform at Vo12.  Connects Vo12 to Vin1 ( COMMON SPEAKER AMPLIFIER block) and input some voice to the microphone. What happened to the speaker?  Answers: 3.  Max amplitude = 15m Vpp. 4.  Noting happened since the output signal Vo12 is too small.

Gas / Ethanol Sensor Unit 4 : KL-64004 13. Gas / Smoke Sensor
Menu

Gas / Smoke Sensor Symbol: Structure: RS Stainless steel double gauze
VC GND VH VR RS Stainless steel double gauze RL Housing NI pin VC: Circuit Voltage Rs: Sensor Resistance VH: Heating Voltage VR: Load Voltage The sensor resistance RS is serially connected to the load resistance RL to form a voltage divider. The VC provides a stable current through the divider and produces a voltage drop across the RL. If the concentration of gas increases, the output voltage VR will increase due to the decrease of sensor resistance RS (the conductivity of the semiconductor inside the sensor increases). As a result, the output voltage VR is a function of gas concentration. Back

Circuit Explanation: V9 = 5 x [R10 / (R9+R10)] V10 V6 V12 RS V8 V14
When gas/smoke detected: Sensor Resistance V6  V12  When V12 > V13  positive voltage output at V14  charging C1  when voltage at C1 (V10) > V9  positive output at V8  555 timer triggered  pulse output at Vo13 When gas/smoke no longer detected: Sensor Resistance V6  V12  When V12 < V13  output LOW at V14  C1 discharging  when voltage at C1 (V10) < V9  output LOW at V8  555 timer disabled  no pulse output at Vo13

With power off, connect Vo13 to Alarm Amplifier SIN. IN Power on the module. Use DCV to record the voltage at V9  Use DCV to record the voltage at V12  Adjust variable resistor R5 so that V13 is 0.5 Volt Higher than V12.  Release some gas to the sensor from a lighter. Observe the voltage change at V12 and V10  What is the condition to increase V10?  What is the condition for buzzer to start alarming?  What is the condition for buzzer to stop alarming?  Use smoke instead of gas, and repeat step 6~9. Note: If the sensor is not used (unenergized) more than 30 days, the sensor resistance will be very low. It will take couple of minutes for the sensor resistance to increase its normal value. Answers: 3.  V9 = ~ 1.6V 4.  V12 = ~ 1.0V 5.  V13 = 1.5V 6.  V12 increases due to V6 increases (sensor resistance decreases)  V10 increases due to V14 increases and charging C1 7.  When V12 > V13, V14 increases and charging C1, so V10 increases 8.  When V10 (voltage at C1) > V9, V8 will trigger 555 Timer 9.  When no gas detected, V14 = Low and C1 start discharging. When V10 lower than V9, the alarm will stop. Note: The answers are used for reference only, the measured voltage is environmental dependent.

Ethanol Sensor Symbol: Structure: RS Stainless steel double gauze VR
VC GND VH VR RS Stainless steel double gauze RL Housing NI pin VC: Circuit Voltage Rs: Sensor Resistance VH: Heating Voltage VR: Load Voltage The sensor resistance RS is serially connected to the load resistance RL to form a voltage divider. The VC provides a stable current through the divider and produces a voltage drop across the RL. If the concentration of ethanol increases, the output voltage VR will increase due to the decrease of sensor resistance RS (the conductivity of the semiconductor inside the sensor increases). As a result, the output voltage VR is a function of ethanol concentration. Back

Circuit Explanation: V6 = 5 x [R24 / (R23+R24)] V5 V6 V3 RS V7 V1
When ethanol detected: Sensor Resistance V6  V3  When V3 > V2  positive voltage output at V1  charging C1  when voltage at C4 (V5) > V6  positive output at V7  555 timer triggered  pulse output at Vo14 When ethanol no longer detected: Sensor Resistance V6  V3  When V3 < V2  output LOW at V1  C1 discharging  when voltage at C4 (V5) < V6  output LOW at V7  555 timer disabled  no pulse output at Vo14

With power off, connect Vo14 to Alarm Amplifier SIN. IN Power on the module. Use DCV to record the voltage at V6  Use DCV to record the voltage at V3  Adjust variable resistor R19 so that V2 is 0.5 Volt Higher than V3.  Put some ethanol on the tissue and rub the sensor surface. Observe the voltage change at V3 and V5  What is the condition to increase V5?  What is the condition for buzzer to start alarming?  What is the condition for buzzer to stop alarming?  Adjust R19 so that V2 is 1 Volt higher than V3, what do you find? Note: If the sensor is not used (unenergized) more than 30 days, the sensor resistance will be very low. It will take couple of minutes for the sensor resistance to increase its normal value. Answers: 3.  V6 = ~ 1.6V 4.  V3 = ~ 1.0V 5.  V2 = ~1.5V 6.  V3 increases due to V6 increases (sensor resistance decreases)  V5 increases due to V1 increases and charging C4 7.  When V3 > V2, V1 increases and charging C4, so V5 increases 8.  When V5 (voltage at C4) > V6, V7 will trigger 555 Timer 9.  When no ethanol detected, V1 = Low and C4 start discharging. When V5 lower than V6, the alarm will stop. 10.  The sensitivity of the sensor becomes lower. Note: The answers are used for reference only, the measured voltage is environmental dependent.

Temperature (AD590) / Humidity Sensor
Unit 5 : KL-64005 Temperature (AD590) / Humidity Sensor 15. Temperature (AD590) Sensor 16. Humidity Sensor Menu

Temperature (AD590) Sensor
Structure: Symbol: + Case - The AD590 is an integrated-circuit temperature transducer which produces an output current proportional to absolute temperature. The device acts as a high impedance constant current regulator, passing 1uA/oK for supply voltages between +4V and +30V. The objective of this module is to convert the 0k scale into 0C so that user can read the value easily. Back

Circuit Explanation: If VR2+R3 = 10k ohm  Vx= I x (R3 + VR2)
= 1uA/0k x 10k = 10mV/0K U1 is voltage follower  V3 = V2 = V6 U3 is voltage follower  U2 is differential amplifier When R10/R11=R5/R4 Example: If room temp is 350C (3080K) Vx = 3.08V = V+ If U3 pin3 is adjusted to 2.73V  V- = 2.73V Vo15 can be obtained Vo15 = (V+ - V-) x 10 = 0.35 x 10 = 3.5 (V)  350C converted to 3.5V Circuit Explanation: (1uA/oK) I 0K=0C+273 V+ V- VCR1 Vx

Using temperature meter to record the current room temperature.  With power off, adjust VR2 so that VR2+R3 is equal to 10k ohm. Power on the module. Use DCV to record the voltage Vx (U1 pin3).  Adjust variable resistor so that Vf1 is equal to 2.73 Volt. Use DCV to record the voltage at Vo15  What may be the reasons that cause the errors?  Adjust VR2 so that the output at Vo15 fits the current room temperature. Use hair dryer to blow both temperature meter and the sensor. Discuss the results.  Use graphic interface software to record the temperature from the computer. Note: If you don’t know how to use graphic interface software, please check Unit 0. Answers: 1.  270C 3.  Vx = 3.01V ( = 3010k = C = 280C ) 5.  Vo15 = 2.93V ( = 29.30C ) 6. (1) The tolerance of the sensor. i.e. I ≠ 1uA/0k (2) The gain the differential amplifier is not equal to 10 due to the tolerance of the resistor. i.e. R10/R11≠R5/R4 ≠10 8.  The value from the module and temperature fits well after adjusting VR2. Note: The answers are used for reference only, the measured voltage is environmental dependent.

Answers: 9.  Level Setup: Option Setup: Use TEMP tag
Background color = yellow if measure value < 35 Background color = blue if 35 < measure value < 45 Background color = pink if measure value > 45

Humidity Sensor Structure: Structures: electrode substrate Lead Wires
Resistive humidity sensors measure the change in electrical impedance of a hygroscopic medium such as a conductive polymer substrate with two separate comb electrodes deposited on. The impedance change is typically an inverse exponential relationship to humidity. Most resistive sensors use symmetrical AC excitation voltage with no DC bias to prevent polarization of the sensor. The resulting current flow is converted and rectified to a DC voltage signal for additional scaling, amplification, linearization, or A/D conversion. Back

Circuit Explanation: U6,R28,C3,R27,C2, and resistance at negative feedback loop consists a Wien bridge oscillator.  Output frequency =1/2π(R27xR28xC2xC3)1/2 = 256 Hz Adjust VR25 for oscillation amplitude. U5 is inverting amplifier, use VR22 to reduce output amplitude. U4 is differential amplifier, use R17 to adjust the gain and use R14 to adjust input offset. CR2, R20, C1 converts the AC signal into DC level. With properly adjusting of the variable resistor in the circuit, the output voltage is able to represent the value of humidity shown below (example): V+ V- Voltage 5V 6V 7V 8V 9V 10V %RH 50 60 70 80 90 100

In this exercise, you need to prepare a humidity meter. Adjust variable resistor R14, R17 and CAL. to center for initial position. Power on the module. Use oscilloscope to measure Vf2 and adjust VR25 until Vf2 obtain the maximum but no distortion oscillation amplitude.  Adjust VR22 until U5 pin6 is equal to 1.75 Vpp. Use a lead wire to short V+ and V- terminal and adjust VR14 until Vo16 is equal to DC 10V.  Remove the lead wire and connect the lead wires of humidity sensor to V+ and V- terminal. Record the value of the current humidity from humidity meter.  Adjust CAL so that the Vo16 is equal to (current humidity value) / 10 Volt. In this case, Vo16 should be equal to 4.8V. Keep breathing out warm air from your mouse/nose to the humidity sensor, what do you observe?  Answers: 3.  Vf2PP= 20V, frequency = 250 Hz. 5.  Since three are no resistance, we assume this situation is 100%RH 7.  48% 9.  Vo16 keep increasing, but the maximum output voltage will not exceed 10V. (9.6V max = 96%RH) Note: The answers are used for reference only, the measured voltage is environmental dependent.

Infrared / Ultrasonic Sensor
Unit 6 : KL-64006 Infrared / Ultrasonic Sensor 17. Infrared Sensor 18. Ultrasonic Sensor Menu

(Infrared Emitting Diode)
Infrared Sensor Symbol: Structure: Transmitter Receiver Anode Cathode Transmitter (Infrared Emitting Diode) Receiver (Photodiode) Infrared emits infrared radiation which is focused by a plastic lens into a narrow beam. The emitting beam of an IR LED is generally proportional to the magnitude of the forward current (forward biased). The beam is modulated i.e. switched on and off, to encode the data. The receiver uses a silicon photodiode to convert the infrared radiation to an electric current for further processing. Back

Circuit Explanation: VLC Vout_U3 Vout_U2
U2: Inverting amplifier, Gain = ~1000 U3: differential amplifier, Gain = ~ 22 U4: Comparator, If V+ > V-  output = 12V || If V->V+  output = -12V Use VR2 to adjusted the output frequency f of the 555 Timer  Q1 switches ON and OFF  Infrared TX emits ON and OFF  If no object blocks between TX and RX  Infrared RX receives ON and OFF  weak pulse signal input to U2  strong pulse signal (Vpp = 12V, frequency = f) output at Vout_U2  At resonant frequency  VLc obtain maximum Vpp  signal amplify again though U3  CR1, C5, R13 converts the AC signal into DC signal at U4 pin3  If U4 pin3 > U4 pin2  Vo17 outputs high potential

Power on the module Use oscilloscope to observe the voltage at VLC and adjust the variable resistor VR2 until Vout_U2 obtain the maximum peak-to-peak voltage. Adjust VR3 until U3 pin3 is 0.3V lower than VLC Record the voltage at U4 pin2 and U4 pin3  Block an object between the sensor, what is the voltage at U4 pin3?  What is the value of Vo17 when nothing block the sensor?  What is the value of Vo17 when the sensor is blocked by an object?  What is the current frequency of the 555 Timer output?  Note: Step 2 and 3 are used for calibration. There are several methods for calibrating this circuit. User can use different methods for calibration but still can obtain the same final result. Answers: 2.  VLC = 0.07V 3.  U3 pin3 = -0.23V 4.  U4 pin2 = 0.85V ; U4 pin3 = 6V 5.  U4 pin3 = 0V. 6.  Vo17 = 11.3V = ON. 7.  Vo17 = -10.2V = OFF 8.  Frequency at U1 pin3 = 0.7 kHz~4.7 kHz Note: The answers are used for reference only, the measured voltage is environmental dependent.

Ultrasonic Sensor Symbol: Structure: Transmitter Receiver
Nominal Frequency: 40kHz Ultrasonic sensors emit and receive a very high frequency sound at 40KHz, which is so high that human can't hear them. Two sensors are identical, but, one as the transmitter and one as the receiver . The transmitter typically sends out a constant beam of sound and the receiver detects any sounds coming in and gives a voltage out. Back

Circuit Explanation (Transmitter):
When S1 OPEN: When S1 CLOSE: VTX VTX １００ 1 1 １０ 1 ０ 1 (?) １ (1) (0) １０ 1 ０ 1 １０１ 1 １ charging C6 U5-a pin2 =1 discharging C6 U5-a pin2 =0 U5-a pin3 =1 U5-a pin3 =1 U5-d pin13 =0 C6 charging/discharging  oscillation C6 fixed, no oscillation Charging C6

Circuit Explanation (Receiver):
VRX Receiver Circuit: Q2 and Q3 forms a cascade amplifier. U6 is a voltage follower CR2 and C8 converts the AC signal to a DC voltage.

Power on the module Put the switch S1 to ON position Use variable resistor R18 to adjust the frequency transmitter so that VRX reaches maximum peak to peak voltage. What is the frequency for at both VTX and VRX point?  Use DCV to measure the output voltage Vo18.  Put an object to block between the sensor, what is the value of output voltage Vo18?  Note: In step 5, there must be no leakage when blocking an object between the sensor. Since the ultrasonic sensor is very sensitive, if there’s a leakage, the output voltage won’t change too much. Answers: 3.  Frequency at VTX = V RX= 40kHz 4.  3.5 Volt 5.  0.2 Volt

Pressure / Strain Gauge
Unit 7 : KL-64007 Pressure / Strain Gauge 19. Pressure Sensor 20. Strain Gauge Sensor Menu

Pressure Sensor Symbol: (Equipment Circuit) Structure:
P1: Forward Gage +VS P2: Backward Gage +Vo 4:Vo- -Vo 1:GND 3:+VS GND 2:Vo+ The pneumatic pressure sensor is based on the piezoresistive (change in conductivity of semiconductors) effect. When a constant-current source is applied to the bridge, the change in resistance will be converted into the change in voltage. Back

Circuit Explanation: Q1 provides fixed current source.
U3 is non-inverting amplifier. Gain = Vf1/V3 = (1+R13/R12) = 2 U3 is used for output voltage (Vo19) adjustment. Since R8 = R14 U1 and U2 are non-inverting amplifier.  Use VR1 to adjust the current through U1 feedback loop (R3)  Use VR5 to adjust the current through U2 feedback loop (R7) VU16 VU26 V3 I When pressure inject into P1 +Vo ; -Vo VU  IR6 VU  Vo19 When pressure inject into P2 +Vo ; -Vo VU  IR6 VU  Vo19

Power on the module Use lead wire to short +Vo and –Vo point. Adjust VR1 so that VU26 is equal to 0 volt. Disconnect the lead wire between +Vo and –Vo. Adjust VR11 so that Vo19 is close to 1500mV. Adjust VR5 for the fine tune so that Vo19 is equal to 1500mV. Use bellows to input air pressure to P1. What’s the status of Vo19?  Use bellows to input air pressure to P2. What’s the status of Vo19?  bellows Answers: 7.  Vo19 is lower than 1500mV. The higher the input pressure, the lower the output voltage 8.  Vo19 is higher than 1500mV. The higher the pressure, the higher the output voltage.

Strain Gauge Symbol: (Equipment Circuit) Structure: +5V Filament Vo-
Lower beam Upper beam Tension cause resistance increase Filament Vo- Vo+ Electrode Tension cause resistance decrease Upper beam Lower beam -5V The strain gauge is a tiny flat coil of conductive wire that changes its resistance when you bend it. The idea is to place the strain gauge on a beam, bend the beam, and then measure the change in resistance to determine the strain. When applying a force from top, the resistance of the strain gauges at upper beam increase while the resistance of the strain gauge at lower beam decrease. Back

Circuit Explanation: When applying force from top:
Vo+ decreases; Vo- increases U4,U5,U6 composes an instrumentation amplifier. R22 is used for output voltage adjustment under null weight condition. When apply force from the top side of the sensor: Vo+ Vo-

Power on the module Adjust variable resistor R24 to center position and than adjust R22 so that Vo20 is equal to 500mV Apply some force from the top of the strain gauge sensor, what happened to the output?  Answers: 3.  Vo20 increases. The stronger the force, the higher the output voltage.

Hall Current / Proximity Sensor
Unit 8 : KL-64008 Hall Current / Proximity Sensor 21. Hall Current Sensor 22. Proximity Sensor Menu

Hall Current Sensor Symbol: Structure: Vin+ V- GND Vin- Output V+
3:V+ (+12V) 1:V- (-12V) 4:Output VH 2:Ground 6:Vin- 5:Vin+ IP IC GND V- Vin- Vin+ V+ Output Hall current sensor, based on Hall Effect technology, provides the output voltage VH proportional to the input current IP (IP = 0~3A  VH = 0~4V) if the control current IC is held constant. Back

Circuit Explanation: VH The characteristic of the sensor is that with input current is IP 0~3A, the output voltage VH is Vo21 0~4V. U1 inverting amplifier  gain = Vo1/VH =- (R2+VR9) / R1  If gain = 0.75  Vo1:VH = -1:1 U2 is inverting amplifier with gain = 1  Vo1:VH = 1:1 There are 3 offset sources in this circuit: (1) Sensor (2) U1 (3) U2  Using VR3 and VR6 to adjust he offset.

In this exercise, you need to prepare a current supply. Power on the module To minimum the offset effect, use lead wire to connect 5:Vin+ and 6:Vin- (zero current input) and adjust VR3 and VR6 so that the output voltage Vo21 is minimum.  Disconnect the lead wire between Vin+ and Vin-. Adjust the output current of current supply to minimum. (Important) Connect current supply current output I+ to Vin+ and I- to and Vin-. Increase the current to 1A and adjust R9 so that Vo21 is 1V. Adjust input current to following value and record output voltage Vo21. (0.25/0.50/0.75/1.0/1.25/1.50/1.75/2.0A )  Note: The input current do NOT exceed 3.0 A Answers: 3.  15mV 4.  When I = (0.25/0.50/0.75/1.00/1.25/1.50/1.75/2.00) A Vo21 = (0.22/0.48/0.74/1.00/1.26/1.51/1.76/2.02) V Good linearity. Note: The answers are used for reference only, the measured voltage is environmental dependent.

Proximity Sensor Structure: Symbol: (Equipment Circuit) Detect Head
VCC Detect Head Output GND LED: Indicator Oscillator Trigger Switching Amplifier Inductive proximity sensors are widely used in various applications to detect metal devices. They consist of an oscillator, trigger, and switching amplifier. If a metal object enters the electromagnetic field of the oscillator coil, eddy currents are induced in this coil which change the amplitude of oscillation, which causes the trigger stage to trip and the semiconductor output stage to switch. Back

Circuit Explanation: Vo When no metallic object approach to the detecting head: Vo = High  Vo22 = Low  Q1 OFF  Buzzer OFF When a metallic object approach to the detecting head: Vo = LOW  Vo22 = High  Q1 ON  Buzzer ON

Insert proximity sensor to 3 pin module socket. Power on the module Use different type of object to approach to the detecting head and observe the result.  Answers: 3.  When metallic type object close to the detect head, buzzer ON.

CDS / Photovoltaic Sensor
Unit 9 : KL-64009 CDS / Photovoltaic Sensor 23. CDS Sensor 24. Photovoltaic Menu

CDS Sensor Symbol: Structure: CaDmium Sulphide (Orange part) Lead
Wires CaDmium Sulphide (CDS) cells, sometimes called photoresistors or photoconductive cells, rely on the material's ability to vary its resistance according to the amount of light striking the cell. The more light that strikes the cell, the lower the resistance. Back

Circuit Explanation: Vin Vo23 When light strikes the CDS :
Sensor resistance  Vin  Q1 (NPN) ON  Q2 (PNP) ON Vo23 High .  LED1 ON When no light strikes the CDS : Sensor resistance  Vin  Q1 (NPN) OFF  Q2 (PNP) OFF Vo23 LOW  LED1 OFF

Power on the module Block the CDS and adjust variable resistor R1 make the LED1 just from the bright to dark. What is the status of the LED1 when the light strikes the CDS? And what is the voltage at Vin?  What is the status of the LED1 when the CDS is blocked? And what is the voltage at Vin?  Use oscilloscope to observe the voltage at Vin, what is the response time when block and unblock the CDS?  Answers: 3.  The LED1 is ON and Vin = 3.6 V 4.  The LED1 is OFF and Vin = 0.1V 5.  Unblock to block: response time = 150ms  Block to unblock: response time = 100ms unblock unblock block Note: The answers are used for reference only, the measured voltage is environmental dependent.

Photovoltaic Sensor Symbol: Structure: Photovoltaic Module
Photovoltaic Cell Photovoltaic, or PV for short, is a technology in which light is converted into electrical power without the aid of any external excitation power. The magnitude of its light-sensitive electrical output signal (current or voltage) is directly proportional to the light intensity it’s exposed to. Back

Circuit Explanation: Ish Vo1 U1 IV Conversion (Vo1 = Ish x (R6+VR7)
If (R6+VR7) is adjusted properly, Vo1 = 0.001V / Lx R8, C1  Low Pass Filter out of 100 or 120 Hz flicker from fluorescent lamp) U2 Voltage follower (Fluorescent lamps which operate directly from mains frequency AC will flicker at twice the mains frequency, since the power being delivered to the lamp drops to zero twice per cycle. This means the light flickers at 120 times per second (Hz) )

Power on the module If you have a illuminometer, check the current lumen. We assume that the current lumen is 500 lx. Adjust variable resistor so that Vo24 is equal to 0.5V. Use oscilloscope to compare the waveform at Vo1 and Vo24. Move the sensor close to the light source, what happened to Vo24? Use graphic interface software to record the measured lumen.  Answers: 4.  5.  The output voltage increases, meaning that the lumen increases. Vo24 Vo1 Vrms = 0.5V 120Hz Note: The answers are used for reference only, the measured voltage is environmental dependent.

Answers: 6.  Level Setup: Option Setup: Use LUX tag
Background color = yellow if measure value < 1000 Background color = blue if 1000 < measure value < 2000 Background color = pink if measure value > 2000

Unit 10 : KL-64010 V/F Converter 25. V/F Converter Menu

V/F Converter Symbol: Structure: Pin14 Pin1 Pin8 Pin7
The voltage-to-frequency (V/F) converters accept a variable analog input signal and generate an output pulse train whose frequency is linearly proportional to the input voltage. Back

Circuit Explanation: From the datasheet :
Rin = R1 = 1M ohm CREF = C2 = 270p farad From the datasheet : VR8 is used to adjust the VREF VR2 is used for fine adjusting output frequency VR11 is used to adjust the input level of comparator U2.

Power on the module. Adjust variable resistor R8 until pin7 of the U1 is equal to -4 Volt. On the KL62001 main unit, connect VR3 to GND, VR1 to +5V, and VR2 connects to Vin. Use DCV to measure the Vin and adjust the potentiometer until Vin is equal to 1V. From the formula with VREF = 4V and Vin = 1V, we can obtain that Fout (Vo25-2) = 926 Hz  Fout/2 (Vo25-1) = 463 Hz Use oscilloscope to measure Vo25-1. Adjust variable resistor R2 until the output frequency is equal to 463 Hz  Calibration Complete Use oscilloscope to record Vo25-1 and Vo  Adjust VR2 on the main unit so that Vin is equal to 2V Compare the result by using formula and oscilloscope.  Connect Vo25-1 to Vin2, what happened to the speaker?  Connect Vo25-2 to Vin2, what happened to the speaker? 

Answers: (7). 7.  Vo25-1(Fout/2) = 463 Hz Vo25-2(Fout) = 926 Hz 9. 
From the formula: Fout = 1852 Hz Fout/2 = 926 Hz From the oscilloscope: Vo25-1(Fout/2) = 929 Hz (9). Vo25-2(Fout) = 1.86 KHz 10.  Speaker output sound with frequency of 929 Hz 11.  with frequency of 1.86 KHz Fout / 2 (square) Fout (pulse) Fout / 2 Fout

Unit 11 : KL-64011 F/V Converter 26. V/F Converter Menu

F/V Converter Symbol: Structure: Pin14 Pin1 Pin8 Pin7
The frequency-to-voltage (F/V) converters accept any input frequency waveform and provides a linearly-proportional voltage output. Back

Circuit Explanation: From the datasheet :
Rint = R10 = 1M ohm CREF = C2 = 150p farad From the datasheet : Note that Resistor, Capacitor and Reference voltage have natural tolerance. U1 is a level shifter. Use VR19 to adjust the input voltage levels. VR2 is used for fine adjusting output voltage U3 is a ripple filter and voltage amplifier. Use VR15 and VR17 for tuning.

In this exercise, you need to prepare a function generator. Power on the module. Adjust variable resistor R19 to center for initial position. Use a lead wire to connect Vin and Ground. Since there are no signal input to the converter, the output voltage should be zero. So adjust variable resistor R6 until Vo26 is equal to 0 V. Disconnect the test lead and Input a 4.3kHz, 2VPP Sine wave to the Vin. Adjust R15 and R17 until Vo26 is equal to DC 4.3V (observe by DCV) and the sawtooth ripple is minimized (observe by oscilloscope, use AC coupling, scale = 100mV). Both conditions should be satisfied.  Calibration Complete. Change the input frequency to 500/1000/1500/2000/2500/3000/3500 and 4000 Hz. What are the corresponding output voltage?  Note: If no input signal detected, use VR19 for input level adjust. Answers: 7.  Vin (Hz) 500 1000 1500 2000 2500 3000 3500 Vo26 (V) 0.498 1.000 1.501 2.003 2.501 3.002 3.504 Good Linearity

Temperature (PT100) Sensor
Unit 12 : KL-64012 Temperature (PT100) Sensor 27. Temperature (PT100) Sensor Menu

Temperature (PT100) Sensor
Symbol: Structure: Stainless-steel protection tube (Platinum wired wound inside) Current In B B’ Voltage Out B’ A B B=B’ A PT-100 is one form of the RTD (Resistance Temperature Detector). It is made of the platinum wire and has the resistance of 100 ohm at 00C. The resistance vs. temperature characteristic of PT-100 can be expressed as: RT = 100 ( T) If constant current I of 2.55mA flow through PT-100 VB’ = I x RT = (255+T)mV Back

Circuit Explanation: VB’ V16 Vo27 Vf1
VB’ = (255+T)mV V16 = ( T)mV V27 = 100T mV VB’ V16 Vo27 Vf1 VR2 is used to control the constant current source to 2.25mV U1 is non-inverting amplifier  V16= ( T) mV U2 is differential amplifier U3 is voltage follower  Adjust VR14 to control Vf1 (offset of U2) So if Vf1 = 2550mV  Vo27 = 100T mV  Conversion Ratio = 100mV / 0C.

In this exercise, you need to prepare a thermometer (mercury) for calibration. Using thermometer to record the current room temperature (T).  Connect 2 lead wires (white) to B and B’, and lead wire (red) to A. Power on the module. Adjust VR2 until VB’ = (255+T)mV  Adjust VR14 until Vo27 is equal to T/10 V (Calibration complete)  Put both PT-100 and the mercury thermometer inside hot water. What is the value shown on the mercury thermometer?  What is the output voltage of Vo27?  Put both PT-100 and the mercury thermometer inside cold water. 11. What is the output voltage of Vo27?  12. What’s the difference between AD590 and PT100 temperature sensor?  Answers: 1.  270C 4.  VB’ = 282mV 5.  Vo27 = 2.70V 7.  54.30C 8.  5.45 Volt (=54.50C) 10.  110C  1.05 Volt (=10.50C) 12.  The response time of PT100 is much slower than AD590. Note: The answers are used for reference only, the measured voltage is environmental dependent.

Unit 13 : KL-64012 Level (Water) Sensor 28. Level (Water) Sensor Menu

Level (Water) Sensor Sensor A,B,C represents 3 levels in Water Tank located at Upper Floor. (short for UFWT) Sensor D,E represents 2 levels in Water Tank located at Bottom Floor. (short for BFWT) A motor is used to pump the water from the BFWT to UFWT. Conditions to be satisfied: (Meanings of w1~w5 is explained in next slide) Anytime when w4 / w5 occurred  Motor stop pumping since BFWT lack of water to pump. When w3 occurred  Motor not pumping since UFWT get enough water. When w3 change to w2  Motor not pumping since UFWT still have enough water When w2 change to w1  Motor start pumping since UFWT lack of water. When w1 change to w2  Motor still pumping since motor will pump until water reach HIGH level When w2 change to w3  Motor stop pumping since UFWT got enough water. w3 w2 w1 Upper Floor Water Tank w5 w4 Bottom Floor Water Tank Back

(I) w1 represents water at UFWT is LOW level
(II) w2 represents water at UFWT is MEDIUM level (III) w3 represents water at UFWT is HIGH level (IV) w4 represents water at BFWT is LOW level (V) w5 represents water at BFWT is HIGH level (I) (II) (III) w3 w2 w1 (Sensor A inside water) Upper / Low (Sensor A B inside water) Upper / Medium (Sensor A B C inside water) Upper / High Upper Floor Water Tank (IV) (V) Note: Use 2 water cups to simulate UFWT and BFWT and use 5 lead wires to simulate water level sensors w5 w4 (Sensor D inside water) Bottom / Low (Sensor D E inside water) Bottom / High Bottom Floor Water Tank

Circuit Explanation (BFWT case):
Vd Vf Vh Vg Vh Vg Vi Va Vb Vc When BFWT/LOW  D,E opened  Va=Low  Vb=High  Vc=Low  Motor OFF When BFWT/HIGH  D,E short  Va=High  Vb=Low  Vc=High  Q2 ON

Circuit Explanation (UFWT case):
Vd Vf Vh Vg Vh Vg Vi Va Vb Vc When UFWT/HIGH  A,B,C short  Vd=High, Vi=High  Vf=Low, Vg=Low Vh=High  Q1 OFF  Motor OFF When UFWT/HIGH >MEDIUM  A,B short  Vd=High, Vi=Low  Vf = Low  Vg=Low since Vh=High from previous status  Q1 OFF  Motor OFF When UFWT/MEDIUM > LOW  A,B,C open  Vd=Low, Vi=Low  Vf=High  Vh=Low  Vg=High  Q1 ON  Motor ON if Q2 ON When UFWT/LOW > MEDIUM  A,B short  Vd High, Vi=Low  Vf = Low  Vg=High since Vh=Low from previous status  Q1 ON  Motor still ON if Q2 ON When UFWT/MEDIUM>HIGH A.B.C short  Vd=High, Vi=High  Vf=Low, Vg=Low  Q1 OFF  Motor OFF

In this exercise, you need to prepare 5 lead wires to simulate A/B/C/D/E sensors and 2 water cups to simulate Upper and Bottom water tank. Use 3 lead wires to connect A,B, and C terminals and put the other end of the three lead wires inside water cup (Upper Tank). Note that all three ends need to be entirely under water. Use 2 lead wires to connect D,E terminals and put the other end of the two lead wires inside another water cup (Bottom Tank). Note that both ends need to be entirely under water. Power on the module, what’s the status of the motor?  Remove lead wire C from upper cup, what’s the status of the motor?  Remove lead wire B from upper cup, what’s the status of the motor?  Remove lead wire E from bottom cup, what’s the status of the motor?  Put lead wire E back to the bottom cup, what’s the status of the motor?  Put lead wire B back to the upper cup, what’s the status of the motor?  Put lead wire C back to the upper cup, what’s the status of the motor?  Answers: 3.  Motor OFF (UFWT full, no need pumping) 4.  Motor OFF (UFWT still have enough water, no need pumping) 5.  Motor ON (UFWT lacks water, need pumping water from BFWT) 6.  Motor OFF (BFWT lack of water to pump to UFWT) 7.  Motor ON (BFWT got enough water to pump to UFWT) 8.  Motor ON (Once starts pumping, motor pumps until water reach HIGH level) 9.  Motor OFF (UFWT full, no need pumping)

Unit 14 : KL-64014 Fiber Optics 29. Fiber Optics Menu

Fiber Optic Symbol: Structure: 1000um core jacketed optical fiber
Receiver: (Phototransistor) Anode Cathode Cathode Anode Transmitter (IR LED) Receiver: (Phototransistor) Transmitter (IR LED) Locking Nut When the fiber optic transmitter (IR LED) is driven by certain amount of current, it emits signal with spectrum peaking at 950 nm. The signal pass through the internal micro-lens and couple into standard 1000 um plastic fiber cable. The signal is then received by fiber optic receiver (phototransistor, 400~1100nm) and converted into electrical signal for further circuit processing. Back

Circuit Explanation: Transmitter Circuit:
High High High Transmitter Circuit: C1, R2 and VR3 charging/discharging at U1b pin4 and pin5 (relaxation oscillator)  U1d and U1C (buffer and driver) On/Off  Q1 On/Off  IR LED blinking  Use VR3 to adjust the output frequency. Receiver Circuit: Receive IR blinking signal  Q2 On/Off  Q2 output waveform sharpen at output of U2-d and U2-c (Vo29).

Cut off the ends of the optical fiber with a single edge razor blade or sharp knife. Try to obtain a precise 90 degree angle. Insert the fiber through the transmitter and receiver locking nut and into the connector until the core tip seats against the internal micro-lens. Screw the connector locking nut down to a snug fit, locking the fiber in place. Power on the module. Connect CH1 of the oscilloscope to the cathode of the transmitter. What is the shape of waveform?  Adjust VR3 until the frequency at cathode of the transmitter is equal to 2kHz. Connect CH2 of the oscilloscope at DATA1, what’s the frequency?  Connect CH2 of the oscilloscope at Vo29, what’s the frequency?  Answers: 5.  Square wave (4.5Vpp) 7.  2kHz (inverting) 8.  2kHz (non-inverting)

Unit 15 : KL-64015 LVDT 30. LVDT Menu

LVDT Symbol: Structure: Stainless Steel Housing Knob
P S1 S2 Knob Ferromagnetic Core Linear Variable Differential Transformer comprises 1 primary coil and 2 secondary coils. When primary coil is energized by a constant amplitude AC source, the magnetic flux thus is coupled by the core to the adjacent secondary coils. The voltage developed at the secondary coils S1,S2 depend on the position of the core. When the core is located at the center (Null Point), VS1=VS2. When the core is located close to the S1 side, more flux is coupled to S1 side, VS1>VS2, and vice versa. Note: The optimum operating frequency for the LVDT using in KL64015 is 350Hz at 5Vrms (14.14Vpp) Back

Circuit Explanation: P S1 S2 U1,R1,C1,R2,C2, and resistance at negative feedback loop consists a Wien bridge oscillator.  Output frequency =1/2π(R1xR2xC1xC2)1/2 = 338.6Hz for energized AC source. R3,R4, VR5, R6 determine the output amplitude. CR1 and CR2 are used to improve the stability of the output amplitude. Q1 and Q2 are used to improve the driver ability. CR3, C4, R10 and CR4, C5, R11 convert the AC output voltage to DC. U2 and U3 are voltage followers which are used as buffers.

Power on the module. Connect oscilloscope CH1 to P terminal and adjust VR5 so that the voltage Vp is equal to 14Vp-p. What is the frequency of the excitation energy of LVDT? Adjust the knob until DC voltage of Vo30-1 and Vo30-2 are equal. Connect oscilloscope CH1 to S1 and CH2 to S2 terminal, what do you find?  Use ruler to measure the total visible length of the screw. What is the outside length of the screw now?  Try to draw the relation between the position of the core and output voltage. What is the resolution of this LVDT?  Answers: 2.  338 Hz. 3.  Vo30-1 = Vo30-2 = 6.2V, the core is located at Null point now. 4.  Two waveforms are identical (Vpp = 14V, f = 338Hz) 5.  Length = ~ 4mm Note: The answers are used for reference only, the measured voltage is environmental senst\itive

Answers: 6.  7.  +0.25V/ mm for Vo30-1  - 0.33V/ mm for Vo30-2
Null point 4.8mm

Rotation Angle Sensor Unit 16 : KL-64016 31. Rotation Angle Sensor
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Rotation Angle Sensor Symbol: Structure: Plastic Housing Knob Vout CCW
Excitation Voltage Vout CCW Output (sliding connection) CW Sometimes called potentiometers, voltage dividers or variable resistors, the precision potentiometric position transducers are widely used in measuring linear distance, angles or rotations in production equipment. It is a three terminal resistor where the position of the sliding connection is user adjustable via a knob. The sensor used in this experiment is a multi-turn potentiometer (10 turns) with an attached reel of wire turning against a spring. Back

Circuit Explanation: U1 (Buffer Amplifier) provides a precision reference voltage at Vf1. U2 (Buffer Amplifier) transfers the voltage from U2pin3 to U2pin6. U4 (Buffer Amplifier) provides fix voltage (adjusted by VR7) at U4pin6 to control the current flow through feedback loop to obtain a stable output at Vo31.

Power on the module Adjust variable resistor VR7 to center for initial position. Rotate the potentiometer from most CCW to most CW position. How many turns is built in the potentiometer?  How many degrees you have rotate in step 2?  Fix the potentiometer at Adjust the variable resistor VR2 until Vo31 is equal to 3.600V. Rotate the potentiometer in CCW direction for 5 turns. Adjust the variable resistor VR7 until Vo31 is equal to 1.800V. Measure and record the output voltage Vo31 for each following turn values. 1/2/3/4/5/6/7/8/9/10 turns Answers: 3.  10 turns 4.  36000 5.  Turns 1 3600 2 7200 3 10800 4 14400 5 18000 6 21600 7 25200 8 28800 9 32400 10 36000 Vo31 (V) 0.359 0.719 1.079 1.440 1.802 2.162 2.522 2.882 3.241 3.601 Good Linearity

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