Fanuc PulseCoder pinout, mising quadrature?

I'm hoping Al & Jon might have some good input here, and anyone else who might have insight.

I have some Fanuc AC aM6/3000 servos (A06B-0162-B076#7000) with red cap pulsecoders, the motor date is 2000.
I've worked through a number of the pinouts out there, and been able to get power and the C1-8 commutation outputs going, but no output from the A/B/Z pins.

The pulsecoder model is A860-0360-V511 (an absolute aA64), No. TT-356675.
I can get some very low-level (mV) sine waves off of the inner test points A & B, but no actual output on the connector.

I did find quadrature output on the test points D0/D8 (same quadrant as PZ, C8,C4,C2,C1, *REQ) but they don't appear on the Amphenol connector. I also get some fun output on the 0deg, 90deg and 180deg test points, so at least I know there are signals passing through the encoder assembly.

I was anticipating needing to connect these through Jon's Fanuc converters, in an attempt to get quadrature and 3-hall, but of course need to be able to connect it up. Given the "A" prefix on the part number, is this one limited to only Absolute and serial?

Does the Absolute variant need either the battery removed (to clear the position memory) or the REQ line strobed (per some prior discussions) to enter a mode to output quadrature?

For correlation, the amphenol pinout most closely matches Jon's reference in that +5 is J,K; Gnd is N,T.

Thanks,
Ted.
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Those are serial absolute encoders (65536 counts/turn) so you would need Jons converter to get quadrature.
The encoder itself only has 2 active signals, REQ and DATA (both differential). For non absolute
use, the battery should make no difference.

Peter - thanks for popping up.
I knew Jon had the commutation converter, I only recently found the "serial" version on his site. A good deal at the price. I did however, put the C1-8, the FZ, D0 and D8 lines on my scope and logic pod, and did get what very much looks like quadrature on D0/D8, and a once-per-rev index on FZ. In the Logic export software, I don't have a way of exporting only a single row per data event, and since I merely rotated the shaft by hand, there were extra data points, but it appears that those test points would send out a 8000 or maybe 8192 counts per rev. (8192 would make sense if it's a 2048 line disc)
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In regards to the C1-C8, I expect I should be seeing those codes sequence 4x per revolution (8 pole motor), of which did happen, and I can use the LCNC BLDC component to build my Hall data for the short term, while I'm making sure the rest of the system is functional.

However, I'm not at all married to a "stock" fanuc motor (ok, 4 of them in the box), and mods to the pulse coder to send out a buffered/differential quadrature and a small PIC or CPLD to change the 4 bit comm to 3Hall wouldn't be too difficult to cobble up and place in the rear cap of the motors. In that regard, it saves the external real estate of extra converter boards.

And to be honest, I'd much rather deal with 8192 CPR than 32K (or whatever Jon's last-best-revision was) any day.

Many thanks,

Ted.

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And to be honest, I'd much rather deal with 8192 CPR than 32K (or whatever Jon's last-best-revision was) any day.

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Not sure why, more counts/turn is pretty much always better

(notice the Fanuc progression from 8000 or so count incremental encoders to 65536 then 1048576 and currently 16M counts /turn serial encoders)

If for no other reason than vastly better velocity estimation

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Originally Posted by PCW_MESA

Not sure why, more counts/turn is pretty much always better

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Yes the more counts per rev the better, make's for a very smooth transition between moves, I did this testing some years ago, & anything below 14Bit Encoder 16384 count per rev, leaves you with jerky transitions when changing direction's Etc, doing anything 3D more the better, that is why Fanuc went to the large count encoders for velocity & smoothness, that it gives the machines