[jlmccuan]

As stated above, my relay board turns on all NO connections when power is supplied to the load. I've put a 10 second delay on the power to the board but it seems to be coming from the load side. This opens my ATC dropping the tool, turns on the mist and flood, extends the toolchanger rack into the spindle if it's down and generally wreaks havok. Any suggestions?

[Jim Dawson]

The power on sequence should be as follows: Computer power, delay everything else until stable. Then Control power. Then E-stop release. Then servo/system enable.

In other words, you should have a manual switch/relay to supply power to the outputs that you switch on after the computer is stable. It is pretty common that the computer will come up in an unstable state and may have the outputs turned on from a cold boot.

I have my E-stops wired to supply power to some outputs on E-stop release, others are not supplied until the enable button is pressed. The E-stop button/relays kills supply power to all outputs.