I always wire shielded twisted pair from MOCMDx and its associated Sig Gnd on the ICM-2900 4-pin block, to +ref & - ref.
Otherwise you are relying on the -ref to wend its way to back to the Galil common Gnd whichever way it can.
Each 4 pin term. block is fitted with a Sig. Gnd terminal.
You will notice the AMC ref recommends this practice.
CNC, Mechatronics Integration and Custom Machine Design (Skype Avail).
“Logic will get you from A to B. Imagination will take you everywhere.”
It runs, all is well in my world. For anyone else with the same issue, follow the AMC brush servo setup instructions below. Especially step 11, my downfall.
5.2 Brush-Type Set-Up Instructions
ADVANCED MOTION CONTROLS amplifiers are designed to operate in a self-test mode, using the "offset"
potentiometer to control an on-board signal source.
This test can be used to confirm that the amplifier is functionally operational. Read the setup instructions before applying
1. Review cautionary notes and wiring section before proceeding.
2. It is recommended to reduce the amplifier output current to avoid motor over heating during the setup procedure.
3. Connect power. Do not connect the motor yet!
4. Make sure the amplifier is in an enabled state via all enable inputs. See amplifier data sheets for details.
5. Check that the LED indicates normal operation (green).
6. Set mode according to data sheet for voltage mode.
7. Set offset/test switch ON. Measure the voltage across motor output with a DC voltmeter, turn the "test" potentiometer.
Voltage should vary between +/- bus voltage. Set the output voltage with the "test" potentiometer to a low value
before connecting the motor leads.
8. Set current limit according to motor specifications. See amplifier data sheets for current limiting options.
9. Verify that the load circuit meets minimum inductance requirements and that the power supply voltage does not
exceed amplifier rated voltage or 150% of the nominal motor voltage.
10. Turn the power off. Connect the motor. Turn the power back on. "Tweak" the "test" potentiometer to change motor
speed in both directions. Set the offset/test switch OFF.
11. Ground both reference inputs and then using the offset pot, set motor for zero speed.
12. Set mode suitable for your application.