Products > Test Equipment
Topward 6303D power supply repair
(1/1)
anton74:
Hello,
I am trying to repair a Topward 6303D power supply.  The SLAVE channel works only in parallel mode with the MASTER channel; in individual mode the SLAVE channel does not respond to its voltage setting potentiometer.  I believe the fault is somewhere in the commutation circuit.  I tried to understand the commutation between the channels; unfortunately, it looks quite complicated.  Attached is the circuit diagram of the unit.  Maybe somebody could explain me the commutation of this device and/or give some directions.  Thanks.
seronday:
I sympathise with you trying to follow the circuit diagram as it is drawn.
The way it is laid out makes it very difficult to see how the control circuit operates.

Some months ago I carried out some repairs to a Topward 6603D power supply, (The 60 volt 3Amp version), which is identical to the 6303D except for the transformer secondary voltage and additional series pass regulation transistors.

I ended up re-drawing some parts of the circuit diagram so that it was easier for me to see how the control circuit operates.

It may take a few days, but I can try to find my notes and hand re-drawn circuits to copy for you if that may help.

Regards.
Smoke Bandit:
Hi, I have one of these Topward PSU's with the master circuit amp control clamped down not allowing the current limit to work. The op amp has been changed so now think it is in the control circuit for the amp. As above, following the circuitry is proving to be a mission. Any chance you could share your redrawn circuit again please?  Thanks and regards
seronday:
@Smoke Bandit.
Appologies for the slow reply.
At present I dont have any electronic copies of my hand drawn circuits.
They were drawn in pencil and do not copy very well in my docunent scanner.
As soon as time permits, I can try to redo them and make a copy for you.

Regards.
Smoke Bandit:
Brilliant, thanks for your reply. Appreciated.
Navigation
Message Index
There was an error while thanking
Thanking...

Go to full version
Powered by SMFPacks Advanced Attachments Uploader Mod