Troubleshooting; Chapter 4: Troubleshooting; Amplifier Related Problems - Aerotech BA10 SERIES User Manual

BA10/20/30 Series User's Manual

CHAPTER 4: TROUBLESHOOTING

In This Section:

Amplifier Related Problems ....................... 4-1

4.1. Amplifier Related Problems
This section covers symptoms, probable causes, and solutions related to BA amplifier
operation. Table 4-1 lists the most common symptoms of irregular operation and the
possible causes and solutions for these faults.
Before performing the tests described in Table 4-1, be aware that lethal voltages
exist on the amplifier's PC board and at the input and output power connections. A
qualified service technician or electrician should perform these tests.
Table 4-1. Amplifier Faults, Causes, and Solutions
Symptom
"ENABLE" LED fails to energize when AC
input power is applied.
Brushless motor will not spin in open loop
current mode.
Motor spins uncontrollably in velocity
mode configuration.
Amplifier faults ( "ENABLE" LED
deenergizes) when motor decelerates.
Motor runs erratic in velocity mode using
encoder for velocity feedback.
Amplifier Faults (Enable LED deenergizes).
Version 1.6
Possible Cause and Solution
1. Insufficient input voltage. Use volt meter to check voltages at "HI" and
"LO" AC input terminals.
2. Short circuit condition at motor connections A, B, and C. Disconnect motor
connections from BA amplifier and check resistance at each terminal relative
to the other terminal. Resistance should read the same for all terminals
(between .5 and 2.0 , depending on motor).
3. Short condition between motor connections and case of motor. Use ohm
meter to check resistance between all motor leads and motor frame (ensure
the motor is disconnected from amplifier). Resistance should read "infinity".
4. Shutdown, P1-10 is not at active state for running amplifier.
5. If amplifier faults, remove AC for 30 seconds.
Motor phases A, B, and C connected incorrectly relative to HA, HB, and HC
hall inputs. See section 2.5 for motor phasing information.
Encoder (sine and cosine) signals or tach (+/-) signals are improperly
connected. Swap connections to change polarity of feedback.
Bus overvoltage detected (BA10/20). This condition indicates an excessive
regeneration condition. The BA10/20 requires that a shunt regulator be
mounted in the unit.
1. The phase of the sine and cosine signal of the encoder is not separated by
90 . The encoder must be adjusted on the motor.
2. Noise on the sine and cosine signals of the encoder. Use a shield or twisted
pair (signal common wrapped around sine and cosine wires) cable between
the motor and the BA amplifier.
1. RMS current exceeded - turn off and then back on, run at lower current.
2. Over temperature condition - Turn off and let amplifier cool down. Provide
better ventilation.
3. Defective on board power supply - Return for repair.
4. Overloaded logic power supply - Remove device(s) being powered from the
BA 5 V supply.
Aerotech, Inc.

Troubleshooting

DANGER
4-1