[Al_The_Man]

I generally use liquid seal flex conduit to run the wiring, So instead of MS 90° I use a 90°
liquid seal fitting and the MS to conduit adaptors made by T&B (Thomas & Betts).
Still pricey but works out cheaper than the MS 90's and the wiring is protected.
Al.

[usfwalden]

how is low rpm torque on induction motors?

I've found a 10hp amc spindle drive they made for fadal which can be configured for either 5krpm max or 7.5krpm max and a fanuc 6s motor which is 5.7kw continuous (7.5hp) 7.5kw 30 min (10hp), 1600rpm continuous 6000rpm 30 min

I'm thinking I could set this combination up with the drive set to the 5k max with 1 to 1 timing pulleys.

The one problem i know of so far is the drive is set up for 1000 line encoder input. The motor has a 2000pulse coder. I guess the easiest thing to do would be to grab the right fanuc pulse coder off ebay. When fanuc lists a 1000 pulse incremental encoder does that mean it's a 1000 line encoder or a 250 line encoder?

Al, what do you think of this set up compared to the 10s servo with the amc b30a40ac drive?

[usfwalden]

Actually, it looks like the 2000p coder is the lowest count coder they made for the 6s

Does anyone make a conversion board?

[Al_The_Man]

I have never used larger than a 5S with a B30A40, I have generally found the limitation to be high accel/decel when pushing the motor size for a particular amp.
The 1000p is 1000 pulses/rev before x4 multiplier.
Al.

[usfwalden]

The drive is huge. It has a dip switch to select for a 10hp or 15hp motor. The question in my mind since I'd be running it 1 to 1 is what is the performance of an induction motor at low rpms compared to a servo motor 1/4 its size?

I have never used larger than a 5S with a B20A40, I have generally found the limitation to be high accel/decel when pushing the motor size for a particular amp.
The 1000p is 1000 pulses/rev before x4 multiplier.
Al.

[Al_The_Man]

I have never experimented down to close to zero like some have with a regular VFD, but I have changed a regular VFD with auto-tune to encoder option, and the result is quite dramatic as regards rpm control.
For a while now Mitsubishi induction motor spindles have had pulse feedback on the motor and an encoder on the final spindle and these position just like a servo for tool change etc.
If the drive is huge, that is not the B30A40 I know!.
Al.

[usfwalden]

no no no no....the b30a40ac is the drive I would use with the 10s servo motor which is a 2.4hp motor.

The amc drive i am talking about for the fanuc 6s spindle is the spindle drive amc made exclusively for fadal. It is for a 10 or 15hp induction motor. Fadal used it on a lot of their machining centers both with and without rigid tapping.

I have never experimented down to close to zero like some have with a regular VFD, but I have changed a regular VFD with auto-tune to encoder option, and the result is quite dramatic as regards rpm control.
For a while now Mitsubishi induction motor spindles have had pulse feedback on the motor and an encoder on the final spindle and these position just like a servo for tool change etc.
If the drive is huge, that is not the B30A40 I know!.
Al.

[Al_The_Man]

The amc drive i am talking about for the fanuc 6s spindle is the spindle drive amc made exclusively for fadal.

Ok, I am not familiar with that one.
Al.

[usfwalden]

What bushing did you use on the gb input shaft?

The GB input shaft measures 1.55" dia.
The Martin timing pulley's are Motor:18H150, GB:20H150.
Almost 1:1, IIRC this was to get a suitable centre distance and maintain belt tension.
I had to fit a 1/2" plate under the motor to raise it slightly.
I think your Excello is a different model?
Al.

[Al_The_Man]

No bushing, I turned the timing pulley out to the shaft size and used the existing keyway.
Al.

[usfwalden]

Ah, do you know anything about the bushings that are standard on fanuc servos? I've seen the same type of bushing on a lot of different fanuc servos on ebay so I'm guessing they are a fanuc thing. They have 4 sections. I got my 10s today and it came with a 36 groove pulley mounted on it--probably a 32mm wide 8mm pitch w type belt. I really like the bushing and pulley but was doubting I could fit an 18 groove pulley on the spindle but from what you are saying maybe I can if I get one that doesn't use a bushing.

No bushing, I turned the timing pulley out to the shaft size and used the existing keyway.
Al.

[Al_The_Man]

I think you are talking about taper lock bushing style, these are used where no keyway is provided.
If you have a keyway it is usually cheaper to go with a plain hub.
Most of the timing pulleys I get are Martin they supply a taper lock style, there are other makes that supply a larger range of metric sizes, probabally Misumi USA may be one.
Al.