Bed not heating

[oak sluice]

My rat rig v4 500 errored out mid l print from a bed not heating as expected.

Today I replaced the SSR and octopus board and still it’s won’t work

I checked the resistance across the white wires and saw 11.9 ohms (likely good for 1200 w)

I tried removing the thermal fuse which tested good at 1ohm and throwing 120 v AC the bed and it heated normally

When I tested the bed heater output I see 3.6 volts on the output when disconnected from the SSR and only 2.1-3V when connected to SSR

I am only measuring 40 volts AC across the white wires when connected to SSR

I tried running the bed output to HE1 (PA3) instead of PA1 and I’m seeing the same 2.1-3v output from the octopus rather than 3.3-3.6

I see 24 volts from the power supply even under load

What am I missing?

[nocturne dune]

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[oak sluice]

Oh I’ll add the bed does heat just incredibly slow and it errors out for not heating as expected since it’s only getting 40V AC

[oak sluice]

Turns out the part cooling fan has a short

That was causing issues on the octopus board

Solved