I´m currently trying to breathe some new life into an old Duplicator 4S which includes an upgrade to an SKR 1.3 Board. The only challenge I´m currently facing is the connection of the Heatbed. The D4S´s heatbed has a total of 6 connectors - 2 power supply connectors and 4 appear to be for the thermocouple. I joined the 3D-printing party fairly late (2018), so all I have ever seen were two connectors for the heatbed thermocouple. That's why I wanted to ask what the two additional ones were for and if anyone knows of an easy way to connect the thermocouple to my beard, which offers only two connectors for the heatbed thermal measurement?
Ok, so according to the following link two of the connectors are common grounds. Does that mean I can simply connect those to a ground pin on my board?https://beta.ivc.no/wiki/index.php/MakerBot_Replicator_1_Upgrades_and_Repairs#Heated_build_platform_connector_replacement
That's what I did with my D4S and it works fine. Just take care not to reuse the Wanhao HBP wires and connectors. These don't seem to be able to handle the load and create quite a bit of electrical noise which messes with the new main board and card reads. I de-soldered the existing connectors and soldered new silicone wires directly to the board. I used a RAMPS board so had to change all my thermocouples to potted thermistors, including the one in the heater bed. I just pasted the thermistor to the bed and covered it with captan tape. Also check the wiring of the stepper motor and drivers. The drivers on the OEM board are soldered upside down so they can't be reused, and the order of the wire pairs can't be copied. You'll need to remap these to your new drivers and keep a careful eye on you stepper temperatures. It was quite a bit of work, but a fun project. No regrets.
Looking at those descriptions id assume both green and yellow go straight to ground and should not have an issue. Can you see where the pins lead to on the main board? Perhaps you can see them joined into one lead along the main board.
Unfortunately I can't be more help with your issue but I'd be very interested to know how you make out with this upgrade! I'd be interested to know what kind of performance improvement you might have
The original machine was quite good and pretty much at the limit of it's mechanical components. I don't think upgrading to a 32bit controller would resolve those problems (ringing and backlash). Being able to print from standard gcode flavours and access to standard componentry are the advantages.
That alone would be worth it for me as I use octoprint and have to use a special plug in that translates the gcode that's frustrating some times. Are you looking to use Marlin?
I used Marlin with good results. I'd be happy to share my code/config if needed.