Fixed! Edited the OP in case you're interested.
Fixed! Edited the OP in case you're interested.
Colleague's mom used this until it supposedly just died. These things have a standby power supply with some logic and a relay that's switching mains, after the board allows it. Circuit of a very similar one, in fact I haven't found any differences yet. Part no. in the defective unit: BCPS-1120 Part no. in pic below BAPS-1120 https://pic8.co/sh/EgQVqk.png
Edit:Main board https://pic8.co/sh/hdizQD.png
Anyway, relay wasn't clicking. No reaction at all when power was applied and power button was pressed. Search revealed that on these the relay that switches mains goes bad. Put a bridge over the NO relay contacts and the unit came on. Sure enough, the 9 V DC relay coil measured open (MegOhms) when desoldered. Hacked in a new relay that I had on hand and no dice. Bridged the contacts and it went into an on-off loop. Now that I write this, it comes to mind that during testing the Standby PSU was floating, not connected to the chassis. Additional info: Cursory testing of the electrolytics revealed nothing out of the ordinary. What I think is unlikely af, is a relay coil going open and after that is fixed, another fault decides to rear its head. Stranger things have happened but not often.
Any kind of input would be much appreciated. I'll pay in a single upboat.
Edit: Fixed! Turns out it was only the relay that was the original problem. The reason for the other problem was that my colleague hat mangled the little plug that connects the five wires from the standby-PSU to the main board and some of the wires weren't making proper contact any more. I ended up removing the cap from the plug and soldering the wires directly to the little contact springs inside. https://pic8.co/sh/pAESCQ.jpg Seems rock solid now.
Old and new relay https://pic8.co/sh/Kuh1lF.jpg
MPOWERD! (active low) state change standby to powered. https://pic8.co/sh/QqXb8Q.png
Colleague's mom used this until it supposedly just died.
These things have a standby power supply with some logic and a relay that's switching mains, after the board allows it.
Circuit of a very similar one, in fact I haven't found any differences yet.
Part no. in the defective unit: BCPS-1120
Part no. in pic below BAPS-1120
https://pic8.co/sh/EgQVqk.png
Edit:Main board
https://pic8.co/sh/hdizQD.png
Anyway, relay wasn't clicking. No reaction at all when power was applied and power button was pressed.
Search revealed that on these the relay that switches mains goes bad.
Put a bridge over the NO relay contacts and the unit came on.
Sure enough, the 9 V DC relay coil measured open (MegOhms) when desoldered.
Hacked in a new relay that I had on hand and no dice. Bridged the contacts and it went into an on-off loop.
Now that I write this, it comes to mind that during testing the Standby PSU was floating, not connected to the chassis.
Additional info: Cursory testing of the electrolytics revealed nothing out of the ordinary.
What I think is unlikely af, is a relay coil going open and after that is fixed, another fault decides to rear its head.
Stranger things have happened but not often.
Any kind of input would be much appreciated. I'll pay in a single upboat.
Edit: Fixed!
Turns out it was only the relay that was the original problem.
The reason for the other problem was that my colleague hat mangled the little plug that connects the five wires from the standby-PSU to the main board and some of the wires weren't making proper contact any more.
I ended up removing the cap from the plug and soldering the wires directly to the little contact springs inside.
https://pic8.co/sh/pAESCQ.jpg Seems rock solid now.
Old and new relay
https://pic8.co/sh/Kuh1lF.jpg
MPOWERD! (active low) state change standby to powered.
https://pic8.co/sh/QqXb8Q.png
You are currently inside a comment thread.
Click here to see all the comments (6).