PDB 24V keeps dying
 

The 24V ports on our PDB keep dying. The green LED stops lighting up after seconds of running our robot. So far we have 3 broken power distribution boards....:mad: An ideas why?

Re: PDB 24V keeps dying
 

Do you drill over your robot causing them to short out often?

Re: PDB 24V keeps dying
 

nope. This is our third PDB and I just changed it 10 min. ago. drove for about a minute and it stopped

Re: PDB 24V keeps dying
 

Is your Crio electronically isolated from your frame?

Re: PDB 24V keeps dying
 

the whole electronics board is on lexan.

Re: PDB 24V keeps dying
 

Yes but lexan can still carry a current for approx. 4-6in. When mounted directly to the frame.

Re: PDB 24V keeps dying
 

what would you suggest for me to do ?

Re: PDB 24V keeps dying
 

When you touch the robot do you might get shocked but when you touch say a bolt on your lexan board do you get shocked? If so you need to isolate your board.

Re: PDB 24V keeps dying
 

heres a picture

Re: PDB 24V keeps dying
 

nope not getting shocked.

Re: PDB 24V keeps dying
 

Garten, I'm very confused by several of your responses in this thread. Do you have data to support your claims that Lexan can conduct electricity 4-6 inches and that the voltages on the robot are sufficient to cause noticeable electric shock?

Jsasaki, verify frame isolation with a meter. Then, check the insulation on the wires coming off the right hand side 40A breakers - you may be shorting there.

Re: PDB 24V keeps dying
 

It would be nice to see the other end of the four pin connecter.

Re: PDB 24V keeps dying
 

Also, those wires touching the Crio from the jag in the upper right corner at touch the Crio and those are getting power.

Re: PDB 24V keeps dying
 

Looks to me like the wire on the 5 volt camera plug is a little long.. Either that, or it's something blocking my view..

Re: PDB 24V keeps dying
 

Yea I saw that too.

Re: PDB 24V keeps dying
 

more pictures

Re: PDB 24V keeps dying
 

In the 24v connector on the PDB, there are four wires connected. Only two should be connected. I see that there are only two wires on the CRIO end. Where are the other two going? It looks like it might be the sidecar. The sidecar should be fed by 12v on a dedicated 20A breaker.

Re: PDB 24V keeps dying
 

I just looked again and it looks like the second set of wires is going to your analog breakout. That should also be powered by a dedicated 12V 20A breaker.

Re: PDB 24V keeps dying
 

The second set of 24v wires feeds the solenoid breakout (properly).

I'd suggest a systematic step-by-step isolation of the problem.
If it's repeatable in a timely manner.

Example given:

1. pull all the power breakers
2. pull the camera and radio power
3. pull the 24v connector

• Turn the system on, see if the 24v power light goes out
• if not:

1. Add in the power breakers

• Turn the system on, see if the 24v power light goes out
• if yes, further isolate the offending breaker
• if not:

1. Add the camera and radio

• Turn the system on, see if the 24v power light goes out
• if yes, further isolate which power causes the problem
• if not:

1. pull the two remaining cRIO modules
2. pull the solenoid power separately from the Breakout
3. Add the 24v power back for just the cRIO chassis

• Turn the system on, see if the 24v power light goes out
• if yes, probably remove the cRIO and do an internal cleaning, per NI directions. Retest.
• if still yes, pull the second set of 24v wires from the connector and retest.
• Check the module pins as well
• if not:

1. Add the Digital module

• Turn the system on, see if the 24v power light goes out
• if yes, test in the alternate digital module slot, as well to see if the problem follows the module.
• if not:

1. Add the unpowered solenoid module

• Turn the system on, see if the 24v power light goes out
• if yes, test in the alternate digital module slot, as well to see if the problem follows the module.
• if not:

1. Add the 24v solenoid Breakout power

• Turn the system on, see if the 24v power light goes out
• if not: (the gremlins have won)