Power reversed on T100MD1616+

[Joel Moore]

Someone hooked up the 24V backwards and I failed to notice for a few seconds.  The only visible damage is the diode at DP6 but the board powers up and I can communicate with it OK (so far).  Outputs are working (haven't tested any inputs yet).

Did I just get lucky?  Can you suggest any components that I should probably replace to avoid a failure down the road?  I suppose that diode is one.

[support]

Apparently DP6 has done its job of shorting out the power supply when power is connected in reverse and therefore protected the rest of the system from permanent failure.  

To ensure that the system will survive long term, put a simple program (such as blinking all the outputs once a second) into the PLC and let it run for 24 to 48 hours. If it doesn't hang after the burn-in period it probably is OK.

[Hhdlp]

New to the tri plcs and have done the same as previous post.

Can the system function with DP6 shorted?  If not, do i have to replace the hole system or can i replace DP6 and continue using it?

[support]

If the DP6 did not suffer an internal meltdown and you put the power back in the correct polarity the board may still work. But if DP6 is already shorted out (use a meter to check both directions) then it has to be replaced. If your output drivers (ULN2803A or ULN2003A) did not short out as a result of the reverse polarity then the board probably is OK, otherwise you will have to replace the failed output drivers which should be quite easy, since they are socketed.

[Hhdlp]

DP6 is definatly gone.  It smoked immediatly and the casing split.  I will be check the other two items you refered to tonight.

Is it possible to get the specs on dp6 so i can get a replacement?  Better yet does tri carry replacements?

edit:   Forgot to say thank you for the immediate reply.

[support]

DP6 part number is 1N4007 but you can use any 1A, 50V or greater rectifier diode. You should be able to get this diode very easily from any electronic components store including Radio Shack.

DP6 is not required for normal operation if you plug in the power correctly. It only works to clamp down the reverse voltage if power supply has been connected in reverse to protect the other components.