Hardware repair of DH-TPC-SD8620N-B50Z30

Fumble

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I've been trying to recover a DH-TPC-SD8620N-B50Z30 via UART but accidentally injected too much voltage and damaged some ICs. I have no schematic and it's a multi-layer board but I think at a minimum the chip that interfaces with ethernet is fried.

Is there anyone reputable I can send the board off to for repair?
 

Fumble

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It does not have a 12V plug? It won't turn on from that supply?
It has a 24VAC input pigtail on the top of the dome. It powers up when I inject 24VAC there, but it no longer establishes an ethernet link or powers up via PoE. I think I fried the main board, picture attached. Thinking of buying a similar model camera used off eBay and swapping the board, re-flashing firmware via UART.

I've been probing around the board and trying to find what I fried. I wasn't aware the dome had a 24VAC to 12VDC power supply hidden away, so I blew up a few components.
 

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tibimakai

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You don't have a thermal camera? I would power it up and inspect it with the thermal to see if anything start heating up. Otherwise, I would start measuring components around the input where you added power. Measure across smd capacitors with the dmm beeper, to see, if it has a short.
 

Fumble

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I have another thermal camera to use for troubleshooting. It's not a short circuit, I blew at least the ethernet driver and other unknown components. I have been testing mosfets, resistors, capacitors, although in-circuit measurements are dicey.

I found a similar optical only camera on eBay made around the same time, I bought it for parts to see if the board can be swapped out. I later realized that the camera dome has a power supply that converts the 24vac down to 12vdc, but the board I pictured does on-board PoE buck conversion.

I found a reputable electronic repair guy who wants $300 to repair it. I'm going to continue to poke and prod, with donor parts, but probably just send it off for repair as this is another project I'll probably never finish.

I did probe this board and the rail I powered went directly to daughter boards and camera modules, which I haven't tested yet. Hopefully I didn't blow them up, too, or I'm left with an expensive pile of junk.
 

knedit2

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that is an extremely expensive fuckup. honestly, take the $300 loss to get it fixed before you risk doing any more hardware damage. if it wasnt a multi-thousand-dollar camera id say keep trying at it but not in this case
 

Fumble

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that is an extremely expensive fuckup. honestly, take the $300 loss to get it fixed before you risk doing any more hardware damage. if it wasnt a multi-thousand-dollar camera id say keep trying at it but not in this case
thanks for the positivity. seems nobody remembers me asking for recommendations of repair shop
 

Fumble

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I was able to resolve this myself. A P821 protection diode in the dome power supply blew and clamped down. I got lucky, after replacing the 4 diodes everything is back up and running to where it was.
 
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