1. CL17 CHLORINE ANALYZER

2. Specifications Theory of operation Installation Operation Maintenance
Outline
Specifications
Theory of operation
Installation
Operation
Maintenance
Troubleshooting
Questions and answers

3. Specifications Operating Range: 0 –5 mg/L Free or Total Chlorine
Accuracy: ±5% or ±0.035, whichever is greater
Resolution: 0.01 mg/L
Detection Limit: mg/L
Cycle Time: 2.5 minutes
Sample Flow Rate (to sample conditioning)
200 – 500 mL/minute ( mL/minute is ideal)
Sample Pressure
1 – 5 psig to instrument
1.5 – 75 psig to sample conditioning
Sample conditioning kit compensates for variance

4. Operating Temperature
Specifications
Alarms
Two SPDT relays
High/Low, System Warning, or System Alarm
Recorder Outputs
One 4-20 mA output
Light Source
LED with a peak wavelength of 520nm
Estimated minimum life of 50,000 hours
Operating Temperature
From 5 – 40oC

5. Monochromator or Filter
Theory of operation
Monochromator or Filter
Lens
Sample
Detector
Lamp
Colorimetry is the measurement of color
The CL17 measures transmitted light at 180 degrees to the light source
The intensity of color relates to the chlorine concentration of the sample
This is a diagram of the major parts of a basic spectrophotometer. The lamp produces light. A single wavelength of light is selected using a monochromator (prism or diffraction grating) or colored filter. It is focused through a lens and directed through the sample. The detector measures the amount of light absorbed by the sample.

6. Theory of operation
In this diagram, the size of the arrows is meant to represent light intensity. This low concentration sample is light in color. As the size of the arrows indicates, the sample absorbs little of the incident light. The sample transmits most of the light shined through it.
In this case, the sample absorbs very little of the incident light
It is a low concentration sample

7. Theory of operation
This high concentration sample is dark in color. As the size of the arrows indicates, this sample absorbs much of the incident light. It transmits little of the light being shined through it.
In this case, most of the incident light is absorbed by the sample
It is a high concentration sample

8. Theory of operation Analysis is a two-step, comparative process.
Zero
Sample cell is flushed with fresh sample
Flow stops and the instrument ‘zeroes out’ any color or turbidity
Read
Reagents added, mixed, and allowed to react
The pink color formed is measured and compared to calibration to determine chlorine concentration
The final results are displayed as mg/L. (milligrams/Liter)

9. Installation
Analyzer is only 12” wide by 19” tall, but there are some things that you should keep in mind…
The door needs to open, so make sure that the analyzer has 16” wide and a clear path 24” in front of it so that the door can be opened.
The sample conditioning kit requires 24” from the top of the analyzer, so leave enough room
There will be connections to power, analog outputs, and relay on the left, and connections for drain and sample lines from the bottom
There are vents on the back of the instrument for the reagent bottles, so leaving a bit of room to prevent vacuums from forming will help

10. Installation

11. Installation Sample line installation
Locate instrument as close as possible to the process (but not too close)
Long sample lines = Long lag time and longer response time to changes in the process
Allow sufficient distance for mixing after chemical addition to process
Minimize response time
Use small diameter tubing to minimize lag time
Route tubing as directly as possible to analyzer
Tap into a pipe from the top
Tap stays completely immersed in sample
Sediment is not drawn in to tap

12. Installation

13. Installation

14. Installation

15. Installation Install reagents Install the stir bar
Mix indicator powder with indicator solution
Invert to mix, do not shake
Install the stir bar
Start flow to the instrument
Power the instrument up with recessed power switch
Prime reagents
Select ‘Menu’ key
Press down arrow until ‘Maint’ appears
Press ‘Enter’
Press down arrow until ‘Prime appears
The instrument will go through 39 accelerated cycles to prime the reagents

16. Maintenance Change reagents monthly Colorimeter cleaning
Both reagents should be changed
Discard reagent remaining in old bottles
Be sure to mix DPD indicator powder with indicator solution
Indicator bottle may turn pink to red over time – this is normal
Colorimeter cleaning
Tubing replacement
Change pump tubing every 6 months.
At operating temperatures above 27oC (80oF), change pump tubing every 3 months.
Replace the remainder of analyzer tubing on an annual basis.
Calibration
Not recommended by Hach
Issues with all three methods (comparison, user prepared, and known standard

17. Maintenance Clean the colorimeter monthly at least
Remove the stir bar with a paperclip
Menu>Maint>Clean interrupts flow through the colorimeter for 60 minutes
Use 2-3 mL (or 2-3 dropper fulls) of 19.2 N acid and leave it in the colorimeter for 45 minutes to allow for the most thorough cleaning
Swab it out before the 60 minutes is up so you still have acid in the colorimeter while swabbing
Replace stir bar and resume normal operation
*** If you have Iron or Manganese in your sample use the following 1 part vinegar to 3 parts hydrogen peroxide to clean using the same steps above

18. Troubleshooting Check flow Check pinch plate
Flow, flow, flow! Incorrect flow is the most common source of customer issues
Make sure that sample is sufficient to the colorimeter. Sample should be approximately 250 mL/min
The location to measure the sample flow is at the elbow below the pump
Check pinch plate
The CL17 measurement cycle is 2 ½ minutes. The first 30 seconds are a full flush of the colorimeter. After the 30 seconds the sample line is pinched closed for 2 minutes and no flow (not even drops) should drip/flow through the sample line.
Disconnect the sample line from the front of the colorimeter. Is sample being cut off during measurement cycle? If not, tighten the pinch plate. If still not turning off, check that the housing is not cracked.

19. Troubleshooting Check that stir bar is installed
Make sure that the stir bar is installed in the instrument. Remove the stir bar with a paperclip.
Ensure that only one stir bar is installed by putting the paper clip back in the colorimeter after removing the first stir bar.
Once the stir bar is removed, attempt to stir sample with the paper clip. If there is a reading, replace the stir bar and monitor.
If instrument still does not read, contact technical support

20. Troubleshooting Verify reagent flow
Verify reagent flow by putting CL17 into prime (Menu>Maint>Prime).
Disconnect reagent lines where they meet in a Y at the front of the colorimeter. Verify you get 1 drop of each reagent/cycle
If no reagent is observed, then reconnect tubing and perform 2 consecutive primes. After this, re-test by putting into prime again, pulling tubes and verifying drops. Keep re-priming until you get flow
If you can’t get flow, then verify reagent tubing has no blockages/kinks/damage. You can also unscrew caps to reagents ¼ turn to release potential vacuum
If reagent is coming out, but you cannot get sample to stop flowing during the measurement, verify the pinch plate is screwed down hand tight and that tubing is in place in all 4 spots behind the pinch plate
Final step is to inspect the back of the pump blocks for wear which can cause a loss of compression for the peristaltic pump action

21. Troubleshooting
System warnings—Indicate a fault condition but the instrument continues normal operation
Low signal (Low Sig) Reference counts are below 2000 A/D counts
Clean the sample cell following outlined procedures
Marginal gain (Marg G) Calibration has resulted in a gain that is above 1.1 or below 0.9
Set the CAL defaults
Recalibrate
Marginal offset (Marg O) High levels of light measured when the LED is off
Check for light leaks

22. Troubleshooting
System Alarms—must be corrected to resume normal operation
EE Error (EE Error) Inability to write to the EE ROM
Press exit key to restart the instrument
Contact Hach technical support if the problem persists
A/D Error (A2D Error) Reference measurements are at 0, indicates that the colorimeter is reading no light at the detector
Remove colorimeter and inspect the connector pins
LED Error (LED Error) Photodetector is reading low levels of light (<100 A/D counts)
Remove the stir bar
Follow cleaning procedure
Replace the colorimeter
Motor failure (Motor Error) Motor’s home position is not detected
Contact Hach technical support team

23. Troubleshooting

24. Troubleshooting

25. Troubleshooting

26. Questions and answers
How can I correct my Chlorine DPD test for interference from oxidized manganese or chromium?
Pretreat your sample with potassium iodide and sodium arsenite as described below. This pretreatment destroys any chlorine in the sample, and allows you to measure and subtract the concentration due only to the manganese or chromium interference.
Adjust at least 25 mL of sample to pH 6-7 using 1 N sulfuric acid or 1 N sodium hydroxide.
Add 3 drops potassium iodide, 30 g/L (Cat. No ) to 25-mL of the pH-adjusted sample.
Mix and wait one minute.
Add 3 drops sodium arsenite, 5 g/L (Cat. No ) and mix. The arsenite destroys any chlorine in the sample but not manganese or chromium.
Pour 10 mL (or the required amount for your instrument or test kit) of the treated sample into a sample cell and add the DPD reagent. Wait 3 minutes if using total DPD reagent. Read the concentration in your instrument or kit.
Subtract this concentration from your original result (without the pretreatment) to find the correct chlorine concentration.

27. Specifications Theory of operation Installation Operation Maintenance
Summary
Specifications
Theory of operation
Installation
Operation
Maintenance
Troubleshooting
Questions and answers