Wireless User Interface for Variable Frequency Drives Team 168 Alex Shuster (EE) Michael Kloter (EE) Christopher Perugini (EE) Kevin Wei (EngPhys - EE) Sponsor: Lenze Advisor: Professor John Chandy

Outline Lenze Existing Problems Deliverables Solution ▫Wireless ▫Hardware ▫Network Topology ▫Transmission ▫Adaptation Budget Project Summary

Lenze Provide Motor Control Solutions Automotive Construction Robotics Manufacturing and Packaging Variable Frequency Drives Speed and Control System for AC motor

Existing Problems and Deliverables Current Problems Hardwired Communication Manually Set Parameters Limited Accessibility Objectives Develop VFD Wireless Interface Maximize Transmission Distance Multi VFD Operation Industrial Grade

Wireless Solution Communication Options: Wi-Fi Bluetooth ZigBee Wireless Communication Choice: ZigBee m / Node Unlimited Range Extension Low Cost Industrial Operation

Hardware Solution B&B Electronics USOPTL4 USB Serial Converter Transforms Serial Signal to RS-485 Sparkfun ATMega128RFA1 MCU and ZigBee Transceiver Combo Cost Effective Compact Size

Hardware Constraints MCU/Transceiver: Communicates using TTL levels VFD requires RS-485 levels Reference Voltage Conflict: RS-485 vs TTL Solution: Breakout Board Switching MCU Code Modification RS-485TTL High Reference Level+200mV Differential3.3V Low Reference Level-200mV Differential0V

Software Stack Solution Basic Data Services Routing Power Management Network Management Data Failure Correction Message Payload Formatting Advanced Security MCU Power Management Hardware Peripheral Interface Lightweight Mesh

Transceiver Scheme Selection Options: FIFO Byte by Byte ▫Buffer vectors inserted in payload frame as received FIFO Message ▫Waits for full message before sent to payload frame Framing Choice: FIFO Byte by Byte Simplicity

Transmission Options Predefined Buffer Size Transmits when buffer filled Variable Buffer Size Transmits when timer triggered Real Time Transmission Transmit data as received

Real Time Transmission Easiest Method: Each data byte transmitted to the VFD once received from the computer Most Convenient Method: Easily adaptable to other applications Will not restrict the use for future products

Indirect Adaptation

Problems: Added Costs RS232/RS485 Converter Bulky Solutions: Direct Adaptation Modify Code to Half Duplex Incorporate GPIO from MCU

Direct Adaptation Tx/Rx Control: Tell RS485/TTL Transceiver when to Send/Receive ▫Incorporate GPIO from MCU

Direct Adaptation

Budget Lenze Grant: $1000 ProductQuantityUnit PricePrice Design Estimates In System Programmer1$35.36 Single Chip MCU and ZigBee Transceiver 3$9.75$29.25 RS-485 to TTL Transceiver 3$2.70$8.10 ZigBee Development Kit1$ RS-232 to RS-485 Converter 3$80.11$ RS-232 to TTL Transceiver 3$18.54$55.62 Misc. Supplies$ Total:$587.66

Project Summary ZigBee PCB Antenna: Easy to tune Reduces Costs MCU Integration: Eliminate External Hardware Wireless Upgrade Package Future Implementation Communication Established Hardwired Connections Eliminated Cost Effective Implementation

Questions