Recent content by rkinner

We had issues with PanelView programming (FactoryTalk View Studio) as it required a 32 bit PC. We got around that when we upgraded by installing VMware operating as a 32 bit system inside the 64 bit Windows 7. I am assuming that your hardware is still able to use the 1784-PKTX card (our new PCs...

I would suggest placing the PID in manual before switching the pumps during a normal switchover. After the new VFD has reached its commanded speed, put the loop back in Auto. My guess is that there will be an upset regardless but this may minimize it as the PID loop won't be trying to...

I've also used a technique where a small set of bits (in PLC-5 a reserved "B" file of maybe 5 words, in ControlLogix a DINT of 2 or 3 words) where it is identified as a "test" bit. With multiple programmers we use some unique ID (say, tags "Russ_test" vs. "Tom_test") so we don't step on each...

Since PLCs are not all made the same, the scanning can differ. For the PLC-5, the scan is 1)read the inputs, 2)execute the logic and then 3)write the outputs. An exception can be made by using immediate update instructions which go out and read a particular module out of sequence for...

ccw has it correct. A modification to that spec I have seen (and used) is to switch the downstream leads at a local motor disconnect. This does not disturb the motor junction box connections but accomplishes the phase reversal quickly. The wiring and labeling between the disconnect and...