i just picked up a Yuasa 5C indexer. It's an old one that looks like the original Hardinge manual indexer with a motor on the side. It has a 7 pin plug. Some basic searching indicates this is a stepper motor type,. Does anyone know the pin outs? Or anyone have a manual for one? I planned on using this initially with a replacement stepper motor and a divisionmaster I have already built. I am now wondering since it is a stepper and not a servo motor if I can use it with the division maser. What kind of stepper uses 7 pins? Any information is appreciated.
Thanks for the replies. I have tried to identify the pins with an Ohmmeter, but I am suspicious my meter is using AC to measure reactance rather than DC to measure the resistance as I can't get a stable value read. The readings jump all over the place and then settle on about 1-2 Ohm. Either way the connectivity is as follows:
A B C D E F G
A X 1 1 Inf Inf Inf Inf
B 1 X 1 Inf Inf Inf Inf
C 1 1 X Inf Inf Inf Inf
D Inf Inf Inf X 1 1 Inf
E Inf Inf Inf 1 X 1 Inf
F Inf Inf Inf 1 1 X Inf
G Inf Inf Inf Inf Inf Inf Inf
I used a Fluke 175 true RMS meter and if anyone knows how t oconfigure it to read the values correctly please let me know.
My guess is that you have a unipolar stepper motor with one winding at pins A-B-C and another winding at pins D-E-F. Pins B and E are likely the center taps. If that is the case, the resistance between A and C should be twice the resistance between A and B.
Pin G is either not connected or grounded (try measuring it to the metal chassis).
"Jumping" readings are to be expected when you are measuring a high inductance coil such as a motor winding. Hold the probes steady and the meter should settle down. It also helps if you select the 600-ohm measuring range manually (using the RANGE button).
I have been advised that the early HAAS indexers and the Yuasa are mechanically and electrically the same; (not the controllers); by a kind chap that gave me a copy of a HAAS manual for the equivalent 5C stepper. If any one would like a copy of that manual its approx 23 MByte, PM me. One nice feature of the manual is that there is a drawing of the tools needed to service the head. From the manual:
"The motor can be tested for shorts with a common ohmmeter if it is able to measure less than 1 ohm. You want to test the connector attached to the motor cable NOT the control. There are seven pins in the motor connector marked A to G. They are hard to see but are marked on the plastic insert inside the connector. The center pin (G) is a ground and should measure infinite (open circuit over 1 megohm) to all of the other six pins. You should also measure between 0.5 ohms and 1.0 ohms between each of the following pairs of pins: A-B, B-C, D-E, and E-F. If any of these are incorrect, the motor is shorted (or open circuit) and the motor should be replaced."
I can't guarantee that the Yausa motor is the same as the Haas motors but it is interesting. I am on the look out for a analogue ohm meter so I can actually measure the values. Thanks for the help so far.
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Yuasa 5C indexer - 7 pin plug
