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Prusa i3 Ramps to Motor wiring, 2015/2016 model

Posted by CrossRoads 
Prusa i3 Ramps to Motor wiring, 2015/2016 model
May 09, 2019 06:22PM
I received a Prusa i3 printer in Jan 2016, just now getting around to assembling it.

Control board for the motor connector is documented as [1A - 1B - 2A - 2B]

The 4 pin connector is Red-Blue-Green-Black (1A, 1B, 2A, 2cool smiley

The motor 6-pin connector however seems to be A --- B - C --- D, with A-C making one coil, and B-D the other coil per a Bechang motor diagram I found,
and confirmed via multimeter with an unconnected motor.
Motors are P/N 17HD40005-22B, BESHENG date code12-14-15

The 6 pin connectors are assembled Red --- Blue - Green --- Black. (or 1A, blank, 1B, 2A, blank, 2cool smiley

Assuming 1A/1B and 2A/2B are the coils, then it seems the motor end needs to be:
Red --- Green - Blue --- Black (1A, blank, 2A, 1B, blank 2cool smiley

Can anyone confirm?
We managed to lose a cable also while it was put aside, so I need to order one. I'd prefer to order a couple with the correct pinout and not fight the pins out of a new housing to make them correct.

I see cables available with both the straight connections, and with the swapped middle pins


Edit - this photo seems to show 1A-1B-2A-2B as red-blue-green-black, and the motor end as red-black-blue-green, or 1A-2B-1B-2A


So some swapping seems to be needed.

Edited 1 time(s). Last edit at 05/09/2019 06:38PM by CrossRoads.
Re: Prusa i3 Ramps to Motor wiring, 2015/2016 model
May 10, 2019 02:23AM
"Assuming 1A/1B and 2A/2B are the coils, "


do not get hung up on colors, stepper motor manufacturers use what ever colors they have at the time and even switch mid runs,
Re: Prusa i3 Ramps to Motor wiring, 2015/2016 model
May 10, 2019 10:56AM
As long as you get the coils right (1A and 2A together, etc.), then things will work, you just have to swap wires on one of the coils to get the stepper to go the right direction.
Yeah, you'll have to wrestle with the connectors, so do NOT buy a bag of 10 cables for $2! Get quality cables and save yourself the grief of dealing with marginal wire gauge for the current and bad crimps. I am big on the "two cables for $6" type of deals. With these, you can easily swap wires by using a single sharp pointy-thing to lift the plastic tab.


Kits: He3D K200 Kossel, Folgertech Kossel 2020 upgraded E3Dv6, Anet A8 upgraded E3Dv6, Tevo Tarantula enhanced parts and dual-head
Scratch: Large bed Cartesian, Linear slide Delta, Maker-Beam XL Micro Delta
Re: Prusa i3 Ramps to Motor wiring, 2015/2016 model
May 12, 2019 08:32PM
Got the wires - made a mistake and didn't measure pin pitch on both ends. Turns out only motor needed 2mm, control board needed 2.54mm. Made one up with a 4-pin crimp housing from Pololu.com (just a pin-friction for now, need a JST type housing for long term use) so we're off & running.

Now seeing a "mintemp" error, while we can use an IR thermoneter and see that things are definitely hot. Waiting for it to cool down and see if we have a bad thermistor.
This is ours, the Electron 3D i3 with the X-axis pieces in yellow instead of black

(not the auto bed leveling tho)

Hmm, measuring the thermistor, it jumps all over the place, vs the bed thermistor which returns a pretty solid reading. Could I have a bad thermistor? If so, is is replaceable? I don't see how one would remove it to install a new one. Do its wires feed in thru the thermistor nozzle? It feels like it just sits loose in an opening.

Update: Got some 100K thermistors on order, arriving tomorrow. We'll see how it goes.

Edited 2 time(s). Last edit at 05/13/2019 08:22AM by CrossRoads.
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