I am using a Duet 2 Ethernet motherboard with RepRap V3.3 and currently have a hotend connected to E0heat (working properly) and a bed heater (requires 120V AC) connected to the bed heat terminal with an SSR (also working properly).
Recently, I added on a chamber heater and read the Duet Documentation for connecting a chamber heater during setup. My chamber heater is a 1000W ceramic air heater that can use 110V or 220V AC. That said, I set up the chamber heater to work with AC mains power through an SSR to the motherboard.
First, I wanted to try connecting the chamber heater to E1Heat (an extra extruder terminal) via its SSR. The duet documentation states that you can do this if your chamber heater uses the same voltage requirement as the board. The motherboard requires 24V DC, of course, and as I mentioned, the chamber heater requires 110V or 220V AC. That said, they are not the same. I knew this initially, though I wanted to test the chamber with a lower voltage input from this terminal to see if I could get it to work properly when directly connected to the board.
As a result of this test, every time I turn on the board and the chamber heater is plugged into AC mains power, the heater immediately starts heating and will not stop until it is unplugged from the mains (even though it is OFF on the interface and has not been activated). I later found that the E1Heat terminal I plugged it into from its SSR was receiving 24V no matter what mode I set (OFF, ON, or STANDBY) and the light showing that extruder heater as "ON" stays lit as well. Even when the chamber heater is not plugged into AC mains the motherboard still sends 24V to this terminal.
Finally, here's my questions on all this:
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From all of my searching on this issue, it seems most likely that I have messed up or blown my MOSFET for this extruder terminal, E1Heat. Can anyone confirm whether it is completely blown or if it is salvageable? Could I reset the board and see if it goes back to normal?
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Is it not possible for me to connect the chamber to the board this way? If so, what other method makes the most sense based on its requirements? I'm doing my best to try to run all my heaters on this one board....
If anyone has any recommendations at all I would really appreciate your thoughts!