Heated Bed Suddenly Not Working.

[BLKKROW]

So today I went to print and the heated bed just doesn't heat anymore. I am using a SSR and I double checked all of my wires and everything is plugged in. My hotend does heat just not the bed.

I am using a Rumba Board, any suggestions? May it be the power supply.

[adamfilip]

same power supply for both?
fuse blown?

[sniffle]

have you checked with a volt meter to check that the power is switching on and off the the SSR, and that the gate on the SSR is functioning? and also, that the PS is supplying 12V then continuity along the lines to see if the wiring has burned up somewhere.

among those checks you should diagnose that its either the board the PS the SSR or the wires themselves.

[BLKKROW]

same power supply for both?
fuse blown?

have you checked with a volt meter to check that the power is switching on and off the the SSR, and that the gate on the SSR is functioning? and also, that the PS is supplying 12V then continuity along the lines to see if the wiring has burned up somewhere.

among those checks you should diagnose that its either the board the PS the SSR or the wires themselves.

Yes its the same PS for both. I will do all of the checks after this print which I had to finish today.

[BLKKROW]

same power supply for both?
fuse blown?

have you checked with a volt meter to check that the power is switching on and off the the SSR, and that the gate on the SSR is functioning? and also, that the PS is supplying 12V then continuity along the lines to see if the wiring has burned up somewhere.

among those checks you should diagnose that its either the board the PS the SSR or the wires themselves.

How would you check the SSR? The voltage difference on the input is 12v but the difference on the out is 0. I am not the best with electronics and want to make sure I am measuring it correctly.

[printbus]

It's hard to provide exact instructions when we don't know exactly how you have the SSR and bed wired. Does the + from the power supply go to the SSR first, or to the bed first?

the difference on the out is 0

Are you seeing 0 across the SSR outputs all the time, or only when the heater/SSR is turned on? The SSR acts like a switch. What you should see is near zero across the outputs when the heater/SSR is turned on, but 12V when the heater/SSR is turned off. If you see 0 all the time, there's an open connection somewhere in your wiring between the power supply, SSR and heat bed or a problem in the heat bed.

The voltage difference on the input is 12v

I assume this is when you've tried to turn the heater on? Does it read near zero when you try to turn the heater off? If so, that confirms that firmware, RUMBA, and the control wiring to the SSR are working.

One easy thing to try would be to temporarily jumper across the SSR output terminals or remove both output connections from the SSR and connect them together. Turn on the printer and see if the bed starts to warm up. If it does, and the SSR control input is known to be working, you pretty much know you have a bad SSR. If the bed still doesn't heat up, there's a problem in either the wiring or the bed itself.

[BLKKROW]

It's hard to provide exact instructions when we don't know exactly how you have the SSR and bed wired. Does the + from the power supply go to the SSR first, or to the bed first?


Are you seeing 0 across the SSR outputs all the time, or only when the heater/SSR is turned on? The SSR acts like a switch. What you should see is near zero across the outputs when the heater/SSR is turned on, but 12V when the heater/SSR is turned off. If you see 0 all the time, there's an open connection somewhere in your wiring between the power supply, SSR and heat bed or a problem in the heat bed.


I assume this is when you've tried to turn the heater on? Does it read near zero when you try to turn the heater off? If so, that confirms that firmware, RUMBA, and the control wiring to the SSR are working.

One easy thing to try would be to temporarily jumper across the SSR output terminals or remove both output connections from the SSR and connect them together. Turn on the printer and see if the bed starts to warm up. If it does, and the SSR control input is known to be working, you pretty much know you have a bad SSR. If the bed still doesn't heat up, there's a problem in either the wiring or the bed itself.

I apologize for not responding sooner but yesterday my computer was taken over by Ransomware the same time my printer stopped working and had to put my printer to the side to get my life back together.

Late last night I found the issue. I was testing every connection for continuity and found that from the PS to SSR I was getting no continuity. So I unscrewed the wire from the SSR and found that the wire oxidized and there was a little burn mark on the SSR plastic. Which is really interesting as I use high quality silicon wire and that is why the plastic shielding didn't melt but the wire experienced a spike in current or volts and become unusable. So I replaced the wire and we are working again.

Here is a picture of the oxidized wire next to what it should look like:

https://scontent.xx.fbcdn.net/hphoto...fe&oe=578C7A03

[BLKKROW]

Just in case if anyone is watching this thread.

So I thought I had the issue resolved but after further testing, when I head the bed I smell burning electronics. So I determined my Solid State Relay is dead as there is a tiny burn mark near one of the terminals.

[ssstraub]

Do you have a link to which SSR you bought and from what source? I might be buying one and am a bit concerned about buying an inferior, cheaply cloned SSR vs a "real" one, considering it's importance and how I'd like my house to not burn down.

[usarmyaircav]

Do you have a link to which SSR you bought and from what source? I might be buying one and am a bit concerned about buying an inferior, cheaply cloned SSR vs a "real" one, considering it's importance and how I'd like my house to not burn down.

No doubt, because I literally just got mine in a few days ago, and only last night mounted it to the cooling fins. Hooking up the wires tonight. I do need to get some silicone wires.