Need Help Converting a Seiko robot to Step/Dir

[Vic Cutter]

I have a Seiko D-TRAN Cartesian Robot that was made in the late 1990’s and I’d like to convert it to use step and direction software like Mach3 software . My question is; would 2 Granite Device VSD-XE DualDC drivers and a Granite Device VSDEPI Parallel interface be a workable solution to this conversion project.

I have the original power supply and the original Servo motors. The specs on the motors are:
X Axis -Tamagawa Seiki Co. Ltd, TRE DC Servo Motor, Type TS1976N101E21, 500 watt, , Encoder 600 C/T, Serial No. AO361, Date: 1993 7, Made in Japan
Internet research has told me that these are 75V motors rated at 3.6A , instantaneous max current 18.1A, Rated speed 3,000min, ?Max speed 4,000min,encoder power source +5V ±5% 200mA Max, These encoders have 9 wires coming out of them colored: Red, Black, Blue, Black, Yellow, Black, Green, Black and black attached to cable shield and the internet motor specs say that the have Tachogenerators attached rated at 6V/1,000min


Y and Z axis motors are both: Model: DH072-200E5N01, Shinano Kenshi Co. Ltd., Made in Japan , no motor specs are shown on the motors but Internet research has told me that these are 200 watt , 75 volt , rated speed 3,000, Encoder rated voltage 24v . These motors both have built in encoders with 9 wires coming out of them colored: Red, Black, Blue, Black, Yellow, Black, Green, Black and black attached to cable shield.

All 3 motors have black and red power wires that have what looks to be a resistor and a small capacitor wired between them.

I would appreciate any comments you experienced CNCer’s have about this project.

[Xerxes]

From motor specs, it sound like VSD DualDC would match them beautifully. A complete control system is easily built from Mach3 + VSDEPI and VSD-E/XE drives.

Encoder voltage should be 5V if connected directly to VSD drive. If encoder doesn't work at 5V, then replacing encoder is probably the easiest solution. A 8192 count/rev encoder costs about $30 so it's not a big deal.

The tachos are not needed as drives use only encoder information. However, it is very important for servo stability that encoders are mounted directly to motor shaft and not anywhere else. In many old machines tachos were used to stabilize servos but in modern systems encoders have replaced them.

The capacitor+resistor thing is probably some sort of snubber circuit and can be left in place.