I'm trying to record the behavior of safety relays over the course several seconds, with various interruptions in between. Basically, I'm doing this: -On for 1s -Off for 1s -On for X time (adjusted) -Off until 3 seconds has elapsed. I have a PLC program to mimic this, amongst others. Originally, in ...

I'm currently using the PicoLog 1000 series to test a relay circuit. However, I have no way of measuring 0 volts. I can't ground it or short it to allow it to see 0 volts. It just jumps around between 0 and 2.5v. Any voltage above 0v works just fine. But the moment it hits 0, it jumps. And if I shor...