Ormerod 2 Heated bed problems

Hi everyone, I am having some issues with regards to the heated bed platform for my Ormerod 2. The bed doesn't seem to work when integrated into the entire system, however works when used with a separate power supply. I have completed all tests stated on the RepRap website and checked that there was no short circuits on the bed contacts. All wiring on Duet is correct and everything else functions correctly. The heated bed goes through spells of operating and turning off, can anyone please shed some guidance on what the issue may be?

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derek5a
Hi everyone, I am having some issues with regards to the heated bed platform for my Ormerod 2. The bed doesn't seem to work when integrated into the entire system, however works when used with a separate power supply. I have completed all tests stated on the RepRap website and checked that there was no short circuits on the bed contacts. All wiring on Duet is correct and everything else functions correctly. The heated bed goes through spells of operating and turning off, can anyone please shed some guidance on what the issue may be?

Does the temp reading for the bed shown in your control program stay at it's set value? I.E 60 degrees C

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Supporting 3D Printers with Parts and Build services.
Printer: Ormerod 2 (528.4) Duel extruder set-up with Aluminium X-Rib, RRPro Firmware v1.11-ch (2016-04-08)

The target temperature in Pronterface works intermittently, but regardless of function the bed does not respond.

Sounds to me like a bad connection. Do you have the version with spade terminals on the bed, or the one with screw terminals? Does the LED next to the heated bed mosfet on the Duet turn on when you command the bed to heat up, even when the LED on the heated bed doesn't turn on?

btw there is a separate forum for the Ormerod.

Edited 1 time(s). Last edit at 01/15/2016 12:38PM 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].

Just to fill you in as there has been some development since last time, the MOSFET on the Duet (version 0.8.5) located next to the power wires for the heated bed has become faulty. We know this as the LED for the MOSFET is always on regardless of power to bed, and smoke was present on one occasion when trying to power up. The heated bed has now been connected to a separate PSU, and the temperature is being measured still with the thermistor through the Duet.

Is this common with the Duet and can you recommend what to do?

We assume the MOSFET is broken and was wondering whether it would be possible to replace this as we need the printer fully operational as soon as possible? Also could there possibly be any other components broken on the Duet as a result of this? However there seems to be no visually evidence. Thanks in advance.

This is the first time I have ever heard of the bed mosfet failing on a Duet of any version. I suggest you get in touch with T3P3 and ask if they will replace either the mosfet or the board.

It should be possible to replace the mosfet, but you will need a hot air rework station to do it. The type is IPD036N04L. Another possibility is to use an external mosfet driven form the pair of pins labelled EXT_FET.

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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].

Okay I will do this and let you know the result as soon as. Thank you for your support so far it has really helped.

Just to update and complete this topic.

Contacted RS (where the kit was purchased). They replaced the Duet board.

New board has been installed and the heated bed is now fully functioning!...

Happy Days!

Still a long way off completing what we need to do but at least now we're working with functioning components!