elevmike
Member
So I just got back from a jobsite where we installed a UPS system that provides 240 vac 1 phase to our control panel. The UPS actually powers a control transformer 500va 240 - 120 vac. The plc is a AD DL 240 CPU. The PLC goes into the run mode but the AC inputs (D2-16NA) don't light up or register an input in the program. I can read voltage applied to the inputs, but can not see them in the program, and the leds don't light. On normal power all is good. Go figure??? I plan on returning to the job with a scope to look at the UPS sine wave. In the mean time any suggestions or comments would be appreciated.
Thanks, Mike.
Thanks, Mike.