Diagnostics
Instruction manual 91/121 V6.3
6.4.10 D.C. Bus under voltage
This alarm appears when the DC BUS voltage drops below the minimum allowed. In this case check:
•
If the power supply is on L1, L2, L3 check the right size of the cables and any transformers upstream of the drive according
to the power required by the motor to operate.
•
If the power supply is on DC+ and DC- check that it is not less than 50Vcc.
6.4.11 Digital Output Over load
This alarm appears when an overload or short circuit occurs on one or more digital outputs. The causes that generate this alarm are:
1. Overload or short circuits on one or more outputs.
2. Capacitive load on one or more exits.
Operations to be carried out:
•
Check the insulation of the connection cables between the drive outputs and the relays or PLC inputs
•
Check the feed data and the absorption of relay or PLC coils
•
Insert a resistance of 100 Ohm 1/2 W in series at each output that drives a capacitive load.
6.4.12 Drive Over current
This alarm appears when the current output from the drive is higher than the maximum allowed value.
The causes of the alarm are:
1. Short circuit on the connecting cables or on the motor windings.
2. Short-circuit or dispersal to the ground of the connecting cables or the windings of the motor.
3. Bad contacts on terminals (oxidised or loose TERMINALS)
4. Susceptible interruptions of the motor connection cables.
5. Current loop time constants too fast.
In this case check:
•
Check the continuity and isolation of the connecting cable between the motor and the drive.
•
Check the status of the TERMINALS and their clamping
•
Check the windings of the motor.
•
Reduce the proportional gain of the current loop (see section ”Pi Current Loop“ from page 52).
Note:
Cable failures are more frequent in the case of mobile installation. motor failures are more likely if they reach high operat -
ing temperatures.
6.4.13 Feedback fault
This alarm appears when the drive detects the failure or error in the signals provided by the transducer mounted in the motor.
The causes of the alarm are:
1. Transducer failure mounted in the motor
2. Incorrect setting of type, data or direction of the transducer
3. Error in transducer and drive links
4. Interruption or short circuit in the connection cable between transducer and motor
5. False contact or failure to insert connectors mounted on the motor and on the drive.
6. Disturbances on the connection cable between transducer and motor.
7. Lack of hall sectors (with TTL encoder or brushless Tacho-generator).
Operations to be carried out:
•
With brushless motor run the AutoTune to check the direction of the transducer.
•
With TTL encoder or brushless tachometer you can check the status of hall sectors with the menu ”Hall sect status“ (see page
45).
•
With DC motor reverse the direction of the transducer.
•
Check the continuity and isolation of the conductors inside the shielded connection cable of the transducer.
•
Check the welds and screen continuity on the motor, intermediate and drive connectors.
•
Check that the cable screen is connected to the ground both on the motor and on the drive.
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Alter Elettronica s.r.l.
