Thread: 24V Light on Power Distribution Board
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Unread 06-02-2011, 18:27
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Re: 24V Light on Power Distribution Board
Quote:
Originally Posted by EricVanWyk View Post
You will most likely need to buy a new PD.

Please disconnect the battery and anything from the 24V. Measure the resistance between the positive lug (where the battery is usually connected) and the positive 24V output. If there is a high resistance, the fuse has been blown.

One way the fuse can be blown is if the 24V positive output is shorted to the negative return for a motor or the battery (shorting to its own negative return does not cause this). This can happen if your chassis is not isolated. Please check to make sure that the chassis of your robot is completely isolated from the electronics - and then make sure it is still true when stuff is getting jostled around.



Matt -

Q12 on page 6 provides reverse polarity protection to the 3 regulated power supplies on the PD.
Ah, I didn't see that. Clever design.

Unfortunately, it seems that the symptoms point towards a short permanently taking out the fuse. I suppose opening the PD up to replace the fuse would constitute a non-competition legal modification?
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