[nova24]

Confusion has set in and I need a little help!

I have a quadrature encoder with the following connections:

Pin A CH A+
Pin B CH B+
Pin C CH A-
Pin D +12 VDC
Pin E CH B-
Pin F GND
Pin G CS/GND

I'm using JP7 for all my axis and encoder hookups, this is so I can relate axis to encoder.

I notice that, for example, JP7 Pins 7 and 8 are for Axis 0 Encoder Input A and B respectively.

Would I hook the encoder up like this:
Enc Pin C to KFlop Pin 7
Enc Pin E to KFlop Pin 8
Enc Pin D to KFlop Pin 3
Enc Pin F to KFlop Pin 25

Any help would be very appreciated.

Thank You!

[TomKerekes]

Hi Dennis,

The KFLOP inputs are 3.3V inputs that can tolerate +5V. Most encoders run from a 5V supply. Yours appears to run from +12V. Do NOT connect 12V outputs to KFLOP. Do you have a specification on your encoder? If not you will need to scope the outputs to see what level they are. They might need pull up resistors. You might be able to reduce the voltage with a voltage divider.

Regards

[nova24]

This is all the spec say's for output:

Output: Square wave outputs – TTL line driver from a MC3487 with 40 ma sink and –40 ma source current available.

[TomKerekes]

In that case it should work. Just to be sure you might want to measure those signals to verify they are less than 5V

The 12V only comes out JP7 pin3 if you feed in 12V to JR1. It is a simple connection through the board and is not used within KFLOP.

Regards

[nova24]

I hooked the encoder up as I outlined in my first post and it's not working. I know the KFlop is only designed to work with single ended encoders and this is a differential encoder. But I've read that I can use the -A, -B connections and not worry about A & B or viceversa.

To your knowledge is this true?

Any suggestions?

[TomKerekes]

Hi Dennis,

Yes you can normally connect a differential output to a single ended input by just using one of the two signals and leaving the other disconnected. Of course you do not have the noise immunity that you get with a real differential input, but it should still work.

You need to do some basic troubleshooting. Did you check if the pins are toggling high and low with a scope or at least a voltmeter? To what voltages? You can also look on the Digital Input Screen to see if the Input bits 0 and 1 are toggling. The screen update rate is too slow to watch individual transitions but when the encoder is moving the bits should be going randomly high and low.

I assume you are watching the Axis Screen to see if the Axis 0 Position is changing?

It is somewhat odd for an encoder that uses a +5V line driver chip to need a +12V supply, so that makes me question if your documentation actually matches your system.

Regards

[cncbaltar]

What if you want the differential output from the Servo driver then what is your recommended method to connect 4 axis to the KFLOP? Currently I own KFLOP + KONNECT.

Yes you can normally connect a differential output to a single ended input by just using one of the two signals and leaving the other disconnected. Of course you do not have the noise immunity that you get with a real differential input, but it should still work.

[TomKerekes]

Hi cncbaltar,

If you don't have our option boards with differential receivers you would need to add external receivers located as close as possible to KFLOP. Some 3rd party vendors sell differential to single ended receiver modules. Such as:

US Digital | Products

HTH
Regards
TK

[cncbaltar]

What board would you recommend from your side for 4 axis? I would probably get added benefit buy just getting another module from you?

I guess thinking about this more I have all the drivers Im assuming you meant the SnapAMP module unless you have something different. will look into the the US digital you showed.

The other option would be to use the +/- 10V signal from my system and add the Kanalog. I have been told this is pretty difficult to setup however.. Let me know if you think one is better than the other?

-Chris

[TomKerekes]

Hi Chris,

What type of motors and drives you you have? Kanalog has 16 differential receivers and would add other I/O but it requires the KFLOP JP7 Connection so if KStep is still needed it would need to connect to KFLOP JP5 and you would lose the extra I/O on KStep.

Regards

[cncbaltar]

I am using the DMM DYN2 with .4kW AC servos. DMM | NEW DYN2 AC Servo Drive | AC SERVO DRIVE | AC SERVO MOTOR | ROTARY ENCODER

[TomKerekes]

It looks like those would accept a +/-10V analog Speed input from Kanalog, but I don't see where the encoder signals are available going back to the controller. Do you see somewhere they are available? What differential encoder signals were you referring to?

Regards

[cncbaltar]

This thing has lots of output options.

JP3 I/O Port - Position Command Input
Connector Type: 3.5mm Pitch Terminal Block
Drive Header: Phoenix MC 1,5/12-G-3,5
Plug Connector: Phoenix MC 1,5/12-ST-3,5
Recommended Wire Gauge: 0.6mm2
(20AWG)
Signal Layout:
Pin 1: GND (Bottom side of drive)
Pin 2: Analog Command Reference ±10VDC
Pin 3: DIR-, B-, CCW- Pulse Reference
Pin 4: DIR+, B+, CCW+ Pulse Reference
Pin 5: STEP-, A-, CW- Pulse Reference
Pin 6: STEP+, A+, CW+ Pulse Reference
Pin 7: Signal Common for Pin. 8, 9, 10, 11.
Pin 8: Alarm Output
Pin 9: OnPosition Output
Pin 10: Absolute Zero Position Index Output
Pin 11: Drive Disable Input
Pin 12: Drive Internal +5VDC Supply (Top side of drive nearest to JP5)

Basically all options for Pins 3,4,5,6 are differential in as the KFLOP only allows for A,B not A+, A-, B+, B-.

You are correct as it looks like I can not use the Analog speed input unless the Encoder signal is found on

JP4 Encoder Feedback Port
Connector Type: 2.54mm Pitch Rectangular
Drive Header: Molex 70553-0038
Plug Connector: Molex 50-57-9404
Recommended Wire Gauge: 0.3mm2
(AWG22)
Signal Layout:
Pin 1: +5VDC Supply
Pin 2: S+
Pin 3: S
Pin 4: Gnd

[TomKerekes]

Hi Chris,

You confused me by saying "Outputs from the drive", but now I believe you were referring to Step/Dir inputs to the drive. If this is the case you don't necessarily need differential drivers to drive the Servo Drive inputs. The Servo Drive inputs are basically LEDs that need to be turned on. Connect the + terminal to +5V and the - terminal to the Step or Direction pin on KFLOP. Configure KFLOP to drive in "Open Collector" mode to sink to GND to turn on the LED.

Regarding encoder feedback from the drive: I don't see it. JP4 on the Servo Drive only has S+ and S-. Not sure what that is. I would expect A+ A- B+ B-.

HTH
Regards

[cncbaltar]

Thanks much!

Sorry about the confusion.. I will just try this in Step/Dir and change things if needed. I will Call DMM and find out what JP4 is referencing with S+ and S-

Thank you again for your support.

-Chris

[Stigoe]

Wouldn't JP4 be the port for connecting the encoder on the motor to the drive? So it is an input port, not an output port?