Power Distribution Board - Red LEDs on

[scherbs17]

This past weekend we wired up the full control system and completed the bench tests without a problem (no red LEDs). The system was handed off to the software team for work. Yesterday I noticed there were some red LEDs lit under some of the terminals. The software team reported that the motors connected to the terminals that had the red LEDs were working just fine.

Has anyone seen this yet? I checked the voltage on each set of terminals and sure enough, one of the pair with the red LED lit read a bit low (10.3V), while another reads a little high (12.4V), and still others right along with the non-lit LED terminals at about 12.2/12.3V.

The schematics on the FIRST site look like a FET may be bad.... that is if the big red 'X' on the schematic (???) doesn't mean the FET was removed in the first place.

I've double checked and triple checked the wiring and fuses. They're all good. We disconnected everything but the PD board and had some of the lights go out... some remain on.

I've included some pictures below and would appreciate any help or suggestions!

PD Loaded w/ red LEDs lit
http://i249.photobucket.com/albums/gg231/scherbs17/PDloaded.jpg

PD Unloaded w/ some red LEDs still lit
http://i249.photobucket.com/albums/gg231/scherbs17/PDnoloads.jpg

Side profile of "good" side of PD board
http://i249.photobucket.com/albums/gg231/scherbs17/PDBadSide.jpg

Side profile of "bad" side of PD board showing possible bad assembly??
http://i249.photobucket.com/albums/gg231/scherbs17/PDGoodSide.jpg

[Al Skierkiewicz]

It sure looks like you received one of the boards with the FETs in place. From your photos, I would expect to see LEDs turned on for any outputs that have no circuit breakers. However, I cannot explain why some are ON and some are OFF. It may be due to manufacturing tolerance in the resistors for the sense circuits. Do the LEDs on the high current outputs turn off when the motors are running? Perhaps someone with more experience using the PD as designed will answer when they see this thread.

[EricVanWyk]

Thats a bit odd. It looks like yours only made it through half the rework. I'll look into it.

[scherbs17]

The LEDs didn't go out when the motors were activated, but two out of three of the LEDs that didn't turn off once all the connections were removed did dim when I reinserted a fuse. They remained dim regardless of motor load.

The board we're seeing this problem on is a second PD board that we picked up from Andymark.biz last week. The original PD board that shipped early (pre-kickoff) is working fine.

[www.divsys.com]

scherbs17-

Intersting find on the LED's, that feature should have been disabled.
*Please contact AndyMark ASAP for an immediate replacement.*

Thank you,
Ben Wrightsman

[scherbs17]

Thanks for all the help guys! Andymark is shipping a new PD board out as we speak.

-Rob Scherbinske