No output from fog machine PCB

[partyanimallighting]

Hi wise ones,
I've got a fog machine that's completely dead, not powering up at all. The model is a Chauvet Geyser RGB and it can be mounted to output upwards, downwards or sideways and it also has an RGB LED output to illuminate the fog in different colors. The PCB controls both the fog output via DMX and the LED output and the colors can be set on the LCD display or controlled via DMX also. I've torn apart the unit and have checked the PCB out a little. The main components consist of the PCB, a separate 36VDC power supply installed next to the main PCB that feeds DC back into this PCB (this DC input voltage probably deals with the LED side of the unit, outputting to the diode plate) and lastly, there's the heater block. On a working unit, on start up, you get a loud relay click, the LED's flash and the display states "HEAT", signalling that the heater is warming up. There are also tiny operating LED diodes that illuminate green and red on the PCB, signalling functionality. But I'm getting nothing out of this one. On powering up, I've checked AC voltage at the input terminals so far and that's fine so there's no problem with the power cord, fuse etc. but when I check voltage at the heater output terminals, it's reading between 8 and 9VAC and none of the LED's on the PCB are illuminated. There is also no click from the relay, which I assuming sends 110VAC to the heater to start the heat up process. The unit apparently also utilizes 2 pumps, a main pump that outputs fog fluid to the heater, and a smaller pump which I believe is used to sense low fluid levels in the reservoir bottle.

Any and all feedback is very welcome.

Party Animal

 

[Bluejets]

Something doen't add up here....
Photo 1 shows the top view of the board with power/heater terminals top left.

Photo 2 shows opposite side of the board with the same terminals on the same side of the board.

To me they should be on the top right when turned over or did you do some negative mirror image thing?

Anyhow, if correct, the heater terminals are shown as direct solder joint to the incoming power (L and N both) so one aspect of your problem must be there.

I don't see how you can be getting 2 different readings from the same terminals unless there is a bad joint there.

I suspect you've taken a wrong turn somewhere with your readings.

 

[davenn]

Thread re-opened

 

[partyanimallighting]

Thanks!! Back to this issue......

 

[partyanimallighting]

Sorry about the first picture. It wasn't properly labeled. Here's the updated picture, properly labeled. And here's my update: The unit also has a separate 36VDC power supply, probably around 2A, which I believe provides separate power for the LED side of the unit but this PS wasn't working, fried fuse. I bridged the fuse, plugged in to check, and the line circuit breaker tripped so this PS has other issues so I condemned it. I found a 28VDC power supply and adjusted it up to 32VDC and I'm assuming this would be sufficient to effect repairs. I connected everything to the PCB with the exception of the pump, fluid sensor, and heater and powered it up. The LED diodes all light up but there is no voltage out of the terminals feeding the heater (hence no activating click from the relay) and nothing on the display. From inception I did change out the BTA16 and the LM7805, assuming these were bad but it's still dead. Any ideas?

 

[partyanimallighting]

And yes, the bottom image was reversed to match up with the top image.

 

[partyanimallighting]