are 5T amps & boards worth anything?

[dave3431]

I am retrofitting my Mazak M5, so I have amps and boards form the main control.
Is it worth putting them on ebay, oh, it also has a BTR but can't find a makers name and have no docs for it. Does anybody want it.

[Dan Fritz]

The 5T controls came with Fanuc 3-phase full wave servo amplifiers, and used either the small Fanuc motors (00, 0, and 5) or the larger (10, 20, 30) motors. The servo amplifiers will be different for the small and the large motors because the SCRs, heat sinks and fuses are bigger for the 10,20,and 30 size motors. Many lathes came with small (0 or 5) motors on the crosslide and a larger motor on the Z axis, so be sure to keep the Amplifier and the motor together as a pair if your motors are different sizes.

The 5T servo amplifiers and motors are compatible with the ones on the very popular 6T, 6M, 10T, 10M, 11T and 11M controllers. They were also used on the previous generation of 2000C and 3000C controls. Since they were so widely used, I would guess that they would be in demand as replacement parts. Look at the companies that repair and sell Fanuc boards and servos to see what they're charging for repaired ones. If yours are in good shape, you should be able to get something for them.

If the BTR board is made by ADR (Advanced Digital Research), then it has some value because it can be used on a lot of other machines. If it's completely unmarked and you have no documentation for it, I would consider it pretty worthless.

[dave3431]

Dan,
Thanks for the info, I had no idea the amps can be used on such a wide range of controls, it's a real shame that they are not +/-10v input or I could have used them in the retrofit.

[Dan Fritz]

These Fanuc drives do accept analog inputs. The small motors (00,0,5) use a 3.5v per 1000 RPM command signal, and the larger motors (10,20,30) use a 7v per 1000 rpm signal. The inputs can go to 10v without losing linearity. The gain is adjustable on the board, so you could use a +/- 10v analog signal if you need to.

The biggest problem with trying to use the Fanuc drives in a retrofit is that the tach signals are usually generated by the CNC using the pulse coder feedback. The pulses are put through a "frequency to velocity" converter so that an analog tach signal is generated for the servo drives, and the need for a real tach generator is eliminated. The tach signals are always 6v per 1000 rpm of the motor. There are some Fanuc motors out there that have tachs in them, and the pulse coders are separately coupled to the ballscrews. Most of the time, however, there are no tachs in the motors and the pulse coder is mounted inside the back cover of the motor. This works fine if your motor is directly coupled to the ballscrew. A few machines have motors with tachs driving the ballscrew with a Gilmer belt, and the pulse coder is directly coupled to the screw.

If you have motors with tachs and separate pulse coders, you should be able to use the servos, motors and pulse coders in almost any kind of retrofit. If the pulse coders are inside the motors, you would need to make some kind of F/V circuit to generate the tach signals, or mount a separate tach generator that's driven at the same speed as the motor.

The CN1 connectors on the Fanuc servo boards have an analog VCMD (velocity command) signal and also a TSA/TSB signal for the tach input. There are also some relay closure signals from the CNC that pull in the servo contactor (PRDY) and enable the firing circuit (ENBL), and there is a contact closure on the servo to confirm that the drive is ready (VRDY).

The sequence is pretty simple. The CNC boots up and closes a contact to send the PRDY (Power ready) signal to the servo. The servo pulls in the big MCC contactor and sends back a contact closure signal to confirm that the velocity unit is ready (VRDY), then the CNC closes the enable signal (ENBL) and you're off and running. The VCMD velocity command analog signal should be clamped to 0v until the servo is enabled, and your tach signal should be live before the ENBL signal is sent. A tach that's missing or backwards polarity will cause a motor to runaway (fast!). A missing phase will cause the motor to run rough and have little power.

Maybe one of the other forum members has cooked up a little F/V converter for generating tach signals for these servos. How about it guys?

[dave3431]

Dan,
The servo motors on my lathe have tacho generators, it say's 6v/1000 rpm on the cover,
size 10 motor on the X axis and size 20 on the Z. The pulse coders are on the end of the ballscrews.
I understand the sequence to enable the amp, but, I am unable to find any identification for the pins on the CN1 connectors.
I have tried to google for documentation on the amps, but drew a blank.
If think, if I had some documentation of the pins, I could work with these amps.

[Dan Fritz]

The CN1 connectors have these signals:

PRDY: CNC sends contact closure between CN1 pin 1 and CN1 pin 14
ENBL: CNC sends contact closure between CN1 pin 2 and CN1 pin 15
OVL: Servo sends contact closure betwen CN1 pin 3 and CN1 pin 16
VRDY: Servo sends contact closure between CN1 pin 4 and CN1 pin 17
Tach signal - analog input to servo between CN1 pin 6 and CN1 pin 19
VCMD signal - analog input to servo between CN1 pin 7 and CN1 pin 20

All other pins are unused.

The contact closure OVL from the servo to the CNC is from the motor overload sensor (the current sensor on the motor armature current that has the little red reset button).

The contact closure VRDY is from a small set of contacts on the side of the big MCC contactor.

[dave3431]

Thanks Dan, I have tested one of the CN1 connectors, it seems that pins 14/15 are wired together, and 19/20 also.
I will do some tentative testing under power this week.

[Dan Fritz]

Pins 19 and 20 are both tied to ground on the board, so the the tach signal on pin 6 and the Velocity command signal on pin 7 are both measured relative to the same ground reference. The check pins CH3 and CH4 are both grounded also, so you should see continuity between pins 19 & 20 and CH3 and CH4

Pins 14 and 15 are both tied to +24vdc on the board, so when the relay contacts on the CNC close for the signals PRDY and ENBL, the +24v from the servo board is put on pins 1 and 2, respectively. This +24v is from the little power supply on the X axis servo board, which also appears at CH15. The Z servo board usually does no have a power supply, since it shares power with the X board through a ribbon cable.

[NZ_Jase]

Hi Dave,

Just saw your post on the retrofit plan. Not sure how far you've got, but I started to go down this track with a Mazak 2L I have. The machine had multiple issues which I have now got on top of, I ended up keeping the original control but found some new parts and am now figuring out the DNC side of things.

I was investigating controllers and decided the DSPMC/IP from VitalSystems was the best fit since it was standalone, had analogue outputs, enough IO channels and was reasonably priced. The only shortfall (at the time) was that there was no threading capability - this module has now been written and included. See the website or there is a forum category on here for the DSPMC/IP that has a lot of info.

Jase.

[dave3431]

Dan,

Thanks for the info on the servo drives, it works.
Can you help me once more, I have an AC spindle drive on my mill, could you tell me the pinout on this drive A06B-6044-H007, thanks.

Dave