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  #1  
Old Fri 27 February 2009, 17:39
rocky2889
Just call me: Rocky
 
San Jose
United States of America
Servo motor encoder wiring - is my diagram correct?

I am trying to wire and test a servo motor with G340 drive. The motor is for test run only. I have an USDigital encoder and it came with 5 wires like this.

#1-ground
#2-index
#3-A Channel
#4-5VDC
#5-B Channel

from the picture diagram, I would wire like this from the G340 drive to the Encoder.

Phases (A) --> A Channel (#3)
Phases (B) --> B Channel (#5)
Encode (-) --> Ground (#1)
Encode (+) --> Index (#2)
-->5+VDC connect to BOB DC5V

Am I right if I following above wiring with the attach picture diagram?

Thanks

Rocky
Attached Images
File Type: jpg BOB.jpg (42.0 KB, 272 views)
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  #2  
Old Sat 28 February 2009, 06:50
Richards
Just call me: Mike
 
South Jordan, UT
United States of America
On my G340 (that I've converted to a G320 by removing the pulse multiplier board), I have Err/Res jumpered to Enc+ and I have a 470 ohm resistor between Enc+ and Enc-.

From the G320 manual:

G320 TERMINAL WIRING
IMPORTANT: When first testing the G320, connect ERR/RES (term. 5) to ENC+ (term. 7). Please follow the next steps in the sequence they are given

ENCODER HOOK-UP
The encoder must be a digital quadrature TTL output type that operates on a single +5VDC power supply. The power supply current rating must be less than 50 mA. It should be at least a 200 line encoder. If the encoder supply current is more than 50 mA, use an external +5VDC supply. IMPORTANT: Connect a 470 ohm resistor from TERM. 6 to TERM. 7 if an external power supply is used for the encoder.
(TERM. 6) ENC- Connect the encoder power supply ground to this terminal.
(TERM. 7) ENC+ Connect the encoder +5VDC to this terminal
(TERM. 8) PHASE A Connect the encoder phase “A” to this terminal
(TERM. 9) PHASE B Connect the encoder phase “B” to this terminal
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  #3  
Old Sat 28 February 2009, 09:08
rocky2889
Just call me: Rocky
 
San Jose
United States of America
Yes, I do have USDigital 500CPR encoder. May be I give a try follow your direction.

But I do I like to able to use the multiplier. Please share information with me if anybody using this G340 drives.

Thanks
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  #4  
Old Sat 28 February 2009, 11:38
Richards
Just call me: Mike
 
South Jordan, UT
United States of America
There are some conditions where the pulse multiplier will cause errors in positioning. When you use very short moves without pausing enough between moves, the pulse multiplier will fail.

It took several tests before I could make the pulse multiplier fail, but as soon as I found the correct test, the pulse multiplier failed every time it ran the test. Because of that, I removed the pulse-multiplier from my G340 and from four of the G212s that I have.

After replacing the pulse-multiplier with the replacement opto-isolator, each device worked properly.
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  #5  
Old Sat 28 February 2009, 13:16
rocky2889
Just call me: Rocky
 
San Jose
United States of America
Ok, I removed the multiplier board. Sorry I am little confused because the problem is the encoder with 5 wires and drive has 4 terminal.

This is what I did and bear with me if I am slow on this.

TERM. 6 ----> Connect to the encoder label "Ground" wire
TERM. 7 ----> Connect to the encoder label "5VDC" wire
TERM. 8 ----> Connect to the encoder label "A Channel"
TERM. 9 ----> Connect to the encoder label "B Channel"

What happen to the wire label "Index" on the encoder wire.


Thanks
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  #6  
Old Sat 28 February 2009, 14:46
Richards
Just call me: Mike
 
South Jordan, UT
United States of America
The Index wire does not have to be connected. It puts out one pulse per shaft rotation. I connected an oscilloscope probe to my indexer wire just to verify that it was working. If you used the motor and encoder with a metal lathe, you would use the index signal when threading.

The G340 will not work without the pulse multiplier board, unless you replace the board with an opto-isolator chip that matches the chip used on the pulse multiplier board.

With the G340 wired as you have it, and with the pulse-multiplier board installed, you should have 2,000 pulses per shaft rotation with a 500 count encoder.

I used a separate 5VDC power supply to supply voltage to the encoder. The G340 does not supply voltage to the encoder.
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  #7  
Old Sat 28 February 2009, 15:57
rocky2889
Just call me: Rocky
 
San Jose
United States of America
Ok, I reinsert the multiplier board back and use an external power supply is this right way to wire?
I connect the 5V- to the TERM. 6 and 5V+ to TERM.7.

TERM. 6 ----> Connect to the encoder label "Ground" wire
^---> Connect to external 5VDC(-)
TERM. 7 ----> Connect to the encoder label "5VDC" wire
^---> Connect to the external 5VDC (+)
TERM. 8 ----> Connect to the encoder label "A Channel"
TERM. 9 ----> Connect to the encoder label "B Channel

Last edited by rocky2889; Sat 28 February 2009 at 16:21..
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  #8  
Old Sun 01 March 2009, 08:04
Richards
Just call me: Mike
 
South Jordan, UT
United States of America
With an external power supply, you will also need to add a 470 ohm resistor between terminal 6 and terminal 7.

After re-reading the Gecko data sheet, it appears that you will not need to use an external 5VDC power supply if your encoder draws less than 50mA. I tried that but it didn't work with my encoder. My encoder requires an aux. 5VDC.
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  #9  
Old Sun 01 March 2009, 09:14
rocky2889
Just call me: Rocky
 
San Jose
United States of America
So if I add 470 ohm resistor to the last wiring I would be okay?

Thanks
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  #10  
Old Sun 01 March 2009, 11:50
Richards
Just call me: Mike
 
South Jordan, UT
United States of America
That's the way that I have my converted G340 wired to my motor and encoder. It works very well, but I have the wrong motor attached to get full performance. The motor is rated at 90 VDC, and I run it at 70V, so I lose 23% of the speed.

What I would like to do is find a good 150 oz*in brushed servo that runs at 4,000 RPM from 70V and then find a good (and inexpensive) 8:1 gearbox. That would give me a motor that would jog at about 13-inches per second with 1,200 oz*in of torque.

The gearbox is the problem. Having a 1-1/2 inch pitch diameter spur gear that spins at a speed over 500 RPM is not needed with a rack and pinion drive.

After much testing, I've decided that until I find a good gearbox that is affordable, the stepper motors can better handle my needs.
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  #11  
Old Sun 01 March 2009, 20:49
rocky2889
Just call me: Rocky
 
San Jose
United States of America
I will give a test tomorrow when I have access to the motor and drive at work. Thanks for the confirmation.
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