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?
Do you drill over your robot causing them to short out often?
nope. This is our third PDB and I just changed it 10 min. ago. drove for about a minute and it stopped
Is your Crio electronically isolated from your frame?
the whole electronics board is on lexan.
Yes but lexan can still carry a current for approx. 4-6in. When mounted directly to the frame.
what would you suggest for me to do ?
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.
nope not getting shocked.
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.
It would be nice to see the other end of the four pin connecter.
Also, those wires touching the Crio from the jag in the upper right corner at touch the Crio and those are getting power.
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…
Yea I saw that too.
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.
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.
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:
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pull all the power breakers
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pull the camera and radio power
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pull the 24v connector
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Turn the system on, see if the 24v power light goes out
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if not:
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Add in the power breakers
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Turn the system on, see if the 24v power light goes out
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if yes, further isolate the offending breaker
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if not:
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Add the camera and radio
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Turn the system on, see if the 24v power light goes out
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if yes, further isolate which power causes the problem
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if not:
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pull the two remaining cRIO modules
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pull the solenoid power separately from the Breakout
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Add the 24v power back for just the cRIO chassis
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Turn the system on, see if the 24v power light goes out
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if yes, probably remove the cRIO and do an internal cleaning, per NI directions. Retest.
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if still yes, pull the second set of 24v wires from the connector and retest.
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Check the module pins as well
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if not:
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Add the Digital module
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Turn the system on, see if the 24v power light goes out
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if yes, test in the alternate digital module slot, as well to see if the problem follows the module.
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if not:
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Add the unpowered solenoid module
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Turn the system on, see if the 24v power light goes out
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if yes, test in the alternate digital module slot, as well to see if the problem follows the module.
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if not:
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Add the 24v solenoid Breakout power
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Turn the system on, see if the 24v power light goes out
*]if not: (the gremlins have won)