Pro/Forums - View Single Post - Damn it. Voltage on 13.8v PSU too high...

JamesAvery22 · 03-06-2006, 08:41 PM

Tried the 1k resistor. On the pumps it dropped the voltage so low they wouldnt spin at all. 5v IIRC. Same for the fan I had. Dropped it to 8a with a fan that pulls 1A at 12v.

Here are some pics of the PCB.

In the first pic:
The two black leads coming from the bottom left come from the transformer.
The white lead that comes from the bottom left feeds ~1v to an LED thats not working
The black lead that comes from behind the PCB comes from the same solder joint that the white and black wire come from, from the bottom right corner.

The white lead that comes right off the bottom of the big white resistor is the +15v output. The white lead that comes from the bottom right corner is the GND.

Chip markings:
The mosfet looking one - TIP29 A7711
8 legged IC - MC1741CP 1 "Motorola insignia" 7707
3 legged diode - 2N 5172
The three black rectangle tab looking ones all have "100" then something that looks like omega then maybe an S. Act like caps.
Had to unsolder the last pic to get it unmounted just to take a pic. - "Motorola insignia" 2N5877 7626

03-06-2006, 08:41 PM	#14
JamesAvery22 Cooling Savant Join Date: May 2004 Location: Northern VA Posts: 383	Re: Damn it. Voltage on 13.8v PSU too high... Tried the 1k resistor. On the pumps it dropped the voltage so low they wouldnt spin at all. 5v IIRC. Same for the fan I had. Dropped it to 8a with a fan that pulls 1A at 12v. Here are some pics of the PCB. In the first pic: The two black leads coming from the bottom left come from the transformer. The white lead that comes from the bottom left feeds ~1v to an LED thats not working The black lead that comes from behind the PCB comes from the same solder joint that the white and black wire come from, from the bottom right corner. The white lead that comes right off the bottom of the big white resistor is the +15v output. The white lead that comes from the bottom right corner is the GND. Chip markings: The mosfet looking one - TIP29 A7711 8 legged IC - MC1741CP 1 "Motorola insignia" 7707 3 legged diode - 2N 5172 The three black rectangle tab looking ones all have "100" then something that looks like omega then maybe an S. Act like caps. Had to unsolder the last pic to get it unmounted just to take a pic. - "Motorola insignia" 2N5877 7626 __________________ Stabbing. My Heatware