Duet Capacitor Near 12V in HOT

I just tried to heat my bed and nozzle to ABS temperatures for the first time to see how my new Duet 0.8.5 would perform and I noticed that the capacitor next to the 12V is very hot to the touch. I know capacitors generally heat up, but is this normal? Should I consider getting a heatsink for this?

Just for reference the capacitor is labeled 100VFK 625

I plan on printing a case and mount for the electronics out of PLA in the next few days and I will have a fan pulling cool air onto the electronics.

Edited 1 time(s). Last edit at 01/21/2016 06:03PM by Pole04.

That capacitor should not get hot. Turn the power off, and check that it has been fitted the right way round. See the photo here [blog.think3dprint3d.com] which presumably shows it the correct way round.

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Pole04
I just tried to heat my bed and nozzle to ABS temperatures for the first time to see how my new Duet 0.8.5 would perform and I noticed that the capacitor next to the 12V is very hot to the touch. I know capacitors generally heat up, but is this normal? Should I consider getting a heatsink for this?

Just for reference the capacitor is labeled 100VFK 625

I plan on printing a case and mount for the electronics out of PLA in the next few days and I will have a fan pulling cool air onto the electronics.

Edited 2 time(s). Last edit at 01/22/2016 04:54AM by dc42.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

The capacitor is definitely mounted on the board correctly.

I was looking over some wiring diagrams for the board and nothing seems perfectly clear online. Is the positive (red wire) bed terminal the terminal closest to the "Power in"? Or is it the furthest?

I looked at the board and it says VIN on the the pin farthest from the "Power In" terminals and Bed- on the pin closest, but all the wiring diagrams online make it look like that should be reversed. I am going to also look at how my bed pcb is wired. This cheap Chinese kit has had many wiring issues that I have found.

Does anyone happen to know which side of the terminal is the Positive for the Bed Heater?

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Pole04
Does anyone happen to know which side of the terminal is the Positive for the Bed Heater?

It's the opposite way round on the Duet 0.8.5 compared to the 0.6. Which way round is described in my blog entry on upgrading my delta printer.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Thank you again! I am had them connected correctly, but it is good to know. I am still seeing a good deal of heat from the mains capacitor when the bed is heating, and when heating the bed for ABS the capacitor gets almost too hot to touch. I am thinking a heatsink and fan may not be such a bad idea.

My Z axis steppers, more cheap Chinese parts, are being replaced. I am done playing around with them. They seem barely able to spin both z-rod reliably, and I have my doubts they will turn the slightly heavier lead screws I just received.. I have ordered a pair of 48mm 2A Nema 17 steppers from Amazon and hope to install them later this week. It is going to require me print some spacers for the feet as there is not enough clearance under the printer to mount the larger steppers at this time. It will be nice to know the exact specs for the motors. I am thinking that new X, Y, and Extruder steppers are not too far off in my future.

I spoke with support at Think3dPrint3d. They were very quick to get back to me!

They stated that this capacitor should not be getting hot and advised that I could keep using the board. If I have a problem they said they would consider it a warranty issue and send a replacement.

I can't say enough how good it is to be dealing with a company with great customer service!

Could it be that the heated bed mosfet near that capacitor is getting hot, and the capacitor is merely picking up heat via the PCB? Electrolytic capacitors don't normally get hot without the vent bursting, which should be visible if it has happened.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].