FP-1000 damage serial port

[Yan Sim]

I am still having problem losing my RS-232 port. Even with an isolated RS-232 board.

I am using RS-232 connection on FP-1000 to connect to my PC serial (RS-232) port.  During my troubleshooting I notice there is about 50Vac between the neutral and the ground. The only way to get rid of the 50 Vac is to ground the neutral. I though that was my problem but after 3 weeks, I fried another RS-232 port.

Any suggestion or advice are welcome.

[Otis]

Hi Yan,

Make sure that your FieldPoint module and your RS-232 communicator are on the same ground plane.  It sounds like what could be happening here is that they are resting on different ground planes.  There is a good chance that if you had 50 Vac on your serial cable that you did damage to one or both devices on either end of your RS-232 cable.  Be careful about just grounding the neutral line, because this could mean you have a direct short between the 50 Vac and ground.  That could definitely serve to damage one or both of your devices or maybe even the cable.

If you do suspect that you damaged your FP-1000 then first try to find and eliminate the reason that it was damaged, then call one of our support engineers so that they can help you get the FP-1000 repaired.

Regards,