I'm in the process of developing a new drive for my '43 round-dial 10EE. Modern electronics with PFC (Power Factor Correction) input stage and full-bridge IGBT output stage. This means a reversible DC motor drive capable of full armature voltage, field weakening, closed loop speed control, etc. Designed for 230VAC single-phase input, although it will actually be able to run as low as 85VAC at reduced output power. Output is designed specifically with the 10EE 3 and 5HP motors in mind, although it will also be capable of driving 3-phase motors. Clean DC output (high frequency switching of DC bus), not the chopped up AC of the cheapy SCR drives. The initial design won't be regenerative, but it will incorporate control of a braking resistor. Not going to be cheap - I estimate bill of material costs will end up around $1500. But, it keeps the original DC motor and backgear vs. spending money on a VFD conversion or the like.
So, here's where I need help... What inputs / outputs does the drive need? Think ideal world, not necessarily limited to only direct retrofit of a 10EE. Here's what I have so far:
I'm sure I'm forgetting something or not aware of some functionality on the newer machines...
Note that this entire effort is open-source hardware and software. I would welcome anyone who wants to contribute to the effort at any level (time and knowledge, not $$$). So far, I have all of the power design complete and am working on the final "logic" board that will have all the smarts and interface I/O - thus the question on I/O needs.
To the same point, anyone is welcome to build their own drive from this design. Obviously the design is not yet complete and documentation is seriously lacking, but what is there (and what will be there) is free for anyone to use or modify for their own purpose. In fact, I would love if I could get a few more people to buy into building one of these drives for themselves. I've ordered 5 each of all the PCBs, so it would be nice if I could recoup some of that cost. If demand is there, I would even consider coordinating a group order / build. Component costs often come down significantly when buying more than 1.
I'll work up some more info if anyone wants to get involved in the design at a lower level. Here are a few links to the circuit design so far. All untested at this point, but I do have boards and parts on order for the first unit.
Input stage power board (essentially a 380VDC, 4800W DC power supply)
CircuitMaker: MonarchDC - Power
Input stage logic board
CircuitMaker: MonarchDC - Logic
Output stage power board
CircuitMaker: MonarchMotor - Power
Thanks!
Greg
So, here's where I need help... What inputs / outputs does the drive need? Think ideal world, not necessarily limited to only direct retrofit of a 10EE. Here's what I have so far:
- Forward switch
- Reverse switch
- Left carriage travel limit switch
- Right carriage travel limit switch
- Left ELSR Switch (ELSR-like function without the need for the actual ELSR mechanical bits)
- Right ELSR Switch
- Primary Speed Control Potentiometer
- Secondary Speed Control Potentiometer for rapid reverse
- Output to drive contactor for braking resistor
- Encoder input for closed loop speed control
I'm sure I'm forgetting something or not aware of some functionality on the newer machines...
Note that this entire effort is open-source hardware and software. I would welcome anyone who wants to contribute to the effort at any level (time and knowledge, not $$$). So far, I have all of the power design complete and am working on the final "logic" board that will have all the smarts and interface I/O - thus the question on I/O needs.
To the same point, anyone is welcome to build their own drive from this design. Obviously the design is not yet complete and documentation is seriously lacking, but what is there (and what will be there) is free for anyone to use or modify for their own purpose. In fact, I would love if I could get a few more people to buy into building one of these drives for themselves. I've ordered 5 each of all the PCBs, so it would be nice if I could recoup some of that cost. If demand is there, I would even consider coordinating a group order / build. Component costs often come down significantly when buying more than 1.
I'll work up some more info if anyone wants to get involved in the design at a lower level. Here are a few links to the circuit design so far. All untested at this point, but I do have boards and parts on order for the first unit.
Input stage power board (essentially a 380VDC, 4800W DC power supply)
CircuitMaker: MonarchDC - Power
Input stage logic board
CircuitMaker: MonarchDC - Logic
Output stage power board
CircuitMaker: MonarchMotor - Power
Thanks!
Greg