220v Inverter Board Testing Following shows the use of the RAV 220v inverter board test procedure for inverter codes 730091000, 710065011, 710590960, 710013740 730090952 and730090954 (Universal). The 730090954 is the latest version with program version GG firmware or higher. Use caution when testing the board- inadvertently unplugging of the Potentiometer connector will result in the sudden activation of the turntable motor at max speed. High capacitive voltages are found on the inverter board. Always unplug the machine from utility power BEFORE removing the inverter cover. WAIT at least 5 minutes after unplugging, to allow the capacitors to discharge, and cycle the pedal up and down before you remove the cover. Evaluation Motor will not rotate- Unplug power and wait 30-45 seconds- Inverter will reset after capacitor discharge. Inverters with firmware GG or older will By-Pass if motor is operated at minimum speed under high load for more than 15-30 seconds. This is normal and prevents overheating of the motor/heatsink. If motor fails to respond to the reset, continue to POT Diagnosis. POT Diagnosis 1. Unplug power 2. Remove side cover to access Potentiometer connector. 3. Check and confirm POT connections are secure- If not, repair and retest. 4. Disconnect POT connector and install test harness (790065030), if available. 2 different style potentiometers are used by RAV: Black oval shaped and a round blue POT. Both POTs are 10,000 ohm and function identically. The black POT has a slightly smaller outside diameter and the plastic locator pin on the shaft side of the POT is closer to the shaft, therefore, the POTs will not readily exchange. Grinding off the locator pin will allow using either POT in any application. *If no test harness is available, back probe the Sense (POT Output) and Ground wires to test POT function: 4 Cavity Connector 6 Cavity Connector Wire# Wire# 3 3 10V DC 1 1 Ground 2 2 Sense (output) X 5 Reverse X 6 Reverse
a. Connect Test Harness Black taped end to Inverter board and Green taped end to POT. Be sure the ribbed part of the male connectors are facing the open slot of the female connectors. Test Harness b. Test Board- Connect 4 or 6 cavity connectors (BE SURE BLUE PIG-TAIL CONNECTOR IS DISCONNECTED FOR VOLTAGE AND RESISTANCE TESTS OF MACHINE COMPONENTS) Test Board c. Plug power back in and install the voltmeter leads into the test port Labeled POT Supply Voltage of test harness or 10V DC and Ground of Test Board. Set scale to 20v DC. Connect power to machine and read voltage. Normal= 9.5v - 10.5v DC
d. If incorrect check: 1. Incoming power source for proper supply voltage at outlet. 2. Proper outlet/cable wiring connections 3. Open neutral and or equipment ground. 4. Check incoming power voltage at inverter (Read Precautions Above). Set voltmeter to 250v AC. 5. Connect leads across Terminals L-N -should read approx 220v. 6. Connect leads, one at a time, from terminal L- Ground terminal (Yellow wire with green stripe marked PE on board) and then N- Ground. Should read approx 110v AC. If all tests are within normal voltages, replace inverter board and retest.
e. Test POT control voltages- *After inverter board or POT replacement 1. With test harness installed, set voltmeter to 20v DC. 2. Measure voltage at test harness port labeled POT Sense or Sense and Ground of Test Board: a. Pedal in neutral position- Approx 3.0v DC b. Pedal in reverse position- Approx 2.0v DC c. Pedal in full forward speed position- Approx 8.0v DC The POT voltage will vary from 3.1v to 7.5v as the pedal is depressed. Sense Voltage- Pedal Neutral Sense Voltage- Reverse Sense Voltage- Pedal Full Forward Trigger Voltages Forward rotation starts at approx. - 4.1v Reverse rotation starts at approx. - 2.25v
The TEST BOARD is also equipped with a bypass potentiometer to use to confirm diagnosis. To use to bypass pot: a. Unplug tire changer. b. Disconnect the potentiometer on the tire changer. c. Plug in the inverter side of the Test Board harness to the inverter, if not already installed. c. Connect the Blue pigtail connectors together. Use test pot to verify motor operation. (keep in mind that slight voltage variances will result in the marks on knob not aligning with exactly with the marks on the board) Potentiometer Adjustment The potentiometer adjustment should be checked under the following conditions: 1. Replacement of inverter board 2. Replacement of potentiometer 3. Motor creep-(turntable continues to turn after pedal is returned to neutral position) 4. Pedal, rack gear or pot gear replacement Adjustment procedure: 1. Unplug power and wait approx 5 minutes. 2. Install test harness as described in POT Diagnosis. 3. Plug power back in and measure sense voltage with pedal in neutral position. Correct voltage- 3.1v DC 4. If necessary, loosen POT driven gear set screw and use small flat head screw driver to adjust POT to read approx. 3.1v DC. **use caution while adjusting POT screw- if POT is inadvertently adjusted passed trigger voltage, the motor will engage unexpectedly.
5. Tighten driven gear set screw and retest. Be sure to unplug and allow capacitors to discharge before removing test harness. Test harness part code 790065030 Set Screw