Outputs: |
|
|
|
NODE ( + ) | NODE | SETUP | MEASUREMENT |
VM |
| 3.75Vdc | |
" | VP = 0 | ||
" | VP = 0 | ||
" | VP = 5 | 4.7Vdc | |
" | VP = 5 | 5.1Vdc | |
" | short | + 7.5Vdc |
If the failure symptoms include output voltage oscillation, check if the CV Error Amp circuit is at fault by shorting
Troubleshooting CC Circuit
The measurements below verify that the operational amplifier circuits provide expected positive and negative dc voltage gain when the CC loop is open and the power mesh shut down.
Circuits Included. Constant Current (CC) Circuit on A2 control board.
Setup. The Main Troubleshooting Setup, Page 53, except connect the external supply with polarity reversed to the unit's + OUT ( - ) and - OUT ( + ) terminals. Apply the ac mains voltage to the isolation transformer. Set the external supply to 3.0Adc constant current with a voltage limit in the range 5 to 20Vdc. Set IP to 0Vdc by connecting to P or set IP to +5Vdc by connecting to
Outputs: |
|
|
|
NODE ( + ) | NODE | SETUP | MEASUREMENT |
IM |
| 0.88Vdc (6030A) | |
|
|
| 0.125Vdc (6031A) |
|
|
| 0.30Vdc (6032A) |
|
|
| 1.00Vdc (6035A) |
" | IP = 0 | ||
" | IP = 5 | +14Vdc |
If the failure symptoms include output current oscillation, check if the differentiator circuit is at fault by removing resistor A2R35. If oscillations stop, the differentiator is probably at fault.
Troubleshooting OVP Circuit
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