Thread: PCM Brownout
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Unread 24-02-2016, 13:07
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Re: PCM Brownout

Quote:
Originally Posted by kan123 View Post
I can answer the questions also since I am also on this team.

We have check the 20 amp fuse.

We are 4 cim drive. For testing this issue we have been on blocks and have also removed breakers for 3 of the cims, so we are powering one cim while on blocks. The issue remains.

We will certainly look at the voltage ramp as a possible solution.

What is puzzling is this never happens when accelerating rapidly, it only occurs when decelerating rapidly.

We appreciate the assistance!!
What is the voltage being reported back to the drivers station.
The dashboard should give you a graph of that info.(I know you said you checked the battery, but this info will help diagnose the issue)
A good fully charged battery should report >12.8 VDC. If the battery is reporting lower than 12.2 VDC then the battery may be not fully charged or may not be good. Even new batteries may not be good.

What type of drivetrain are you using?
Going from full forward to stop may cause the CIMs to stall, depending on the mass of the drivetrain. This will be made worse by reducing the number of CIMs to 1. A single stalled CIM should not cause an issue, but knowing this again will help diagnose the issue.

When the compressor first kicks on it may draw more than 20 amps (inrush current). This should not trip the snap action breaker since that current draw is for such a short period of time but you might want to check the current of the compressor.
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