Baldor mn722 manual Inverter Section Troubleshooting

Table 5-4 Inverter Section Troubleshooting Continued

INDICATION	POSSIBLE CAUSE			CORRECTIVE ACTION
Motor has wrong	Analog input common mode voltage	Connect control input source common to control common to minimize
response to	may be excessive.	common mode voltage. Maximum common mode voltage at terminals
Speed Command		J1-4 and J1-5 is ± 15VDC referenced to chassis common.
	Incorrect MIN or MAX speed	Check Level 2 Output Limits block, MIN Output Speed and MAX Output
	settings.	Speed parameter values and adjust as needed.
	Analog offset trim is incorrectly set.	Re-run “Offset Trim” autotune test.
	Speed gain value is too large.	Reduce the Level 1 Vector Control block, Speed PROP Gain and
		Speed INT Gain parameter values.
Motor Shaft	Incorrect encoder alignment	Change the Feedback Align parameter in the Level 1 Vector Control block.
Oscillates back	direction.	If Reverse, set to Forward. If Forward, set to Reverse.
and forth
Motor Shaft	Incorrect encoder alignment	Check encoder connections.
rotates at low	direction.	Change the Feedback Align parameter in the Level 1 Vector Control block.
speed regardless		If Reverse, set to Forward. If Forward, set to Reverse.
of commanded
speed
Motor Shaft	Incorrect encoder wiring.	Reverse the A and		or B and		encoder wires at the J1 input to control
			A		B
rotates in wrong		and change encoder direction in the Feedback Align parameter in the
direction		Level 1 Vector Control block.
Motor Will Not	Not enough starting torque.	Increase Current Limit setting.
Start
	Motor overloaded.	Check for proper motor loading.
		Check couplings for binding.
		Verify proper sizing of control and motor.
	Motor may be commanded to run	Increase speed command or reduce minimum speed setting.
	below minimum speed setting.
	Incorrect Command Select	Change Command Select parameter to match wiring at J1.
	parameter.
	Incorrect speed command.	Verify control is receiving proper command signal at J1.
Motor Will Not	Max Output Speed set too low.	Adjust Level 2 Output Limits block, MAX Output Speed parameter value.
Reach Maximum
	Motor overloaded.	Check for mechanical overload. If unloaded motor shaft does not rotate
Speed
		freely, check motor bearings.
	Improper speed command.	Verify control is set to proper operating mode to receive speed command.
		Verify control is receiving proper command signal at input terminals.
		Check velocity loop gains.
	Speed potentiometer failure.	Replace potentiometer.
Motor Will Not	MIN Output Speed parameter set	Adjust MIN Output Speed parameter value.
Stop Rotation	too high.
	Improper speed command.	Verify control is receiving proper command signal at input terminals.
		Verify control is set to receive speed command.
	Speed potentiometer failure.	Replace potentiometer.
	Analog input common mode voltage	Connect control input source common to control common (J1-1) to
	may be excessive.	minimize common mode voltage. Maximum common mode voltage at
		terminals J1-4 and J1-5 is ± 15VDC referenced to chassis common.
	Analog offset trim set incorrectly.	Re-run “Offset Trim” autotune test.
		Adjust the Level 1 Input block, ANA CMD Offset parameter to obtain zero
		speed.

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MN722 Troubleshooting 5-11