pmdx - 105 for plasma trigger

[swgr]

Hi, I'm thinking of adding a powermax 45 plasma torch to my current setup which includes pmdx 126 and ess. I will eventually be using a torch height controller THC. The plasma cutter requires a dry contact  to trigger to arc (18VDC Normal Open on the plasma end, shot to start the arc).

To trigger the plasma would the PMDX-105 connected to a standard output be a good choice as it provides additional layer of optical isolation and has a fast response time of 2 ms?  Or would I be better off using the relay on the pmdx 126 board?

[Steve Stallings]

While the PMDX-105 should work for this application, there is no need for the extra speed.

Things in the startup of a plasma system happen in the tens of millisecond range and a plain mechanical relay works fine. Indeed, most dedicated plasma controls use mechanical relays.

You should be fine using one of the relays on the PMDX-126 itself.