Fuji Electric BUC S-69D, Инструкция по эксплуатации

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[ 2 ] Overvoltage
Problem The DC link bus voltage exceeded the overvoltage detection level.
Possible Causes What to Check and Suggested Measures
(1) Braking load was too heavy.
Compare the braking torque of the load with that of the inverter.
 Increase the deceleration time of the inverter.
 Decrease the moment of inertia of the load.
 Enable the torque limiter of the inverter.
(2) Malfunction caused by noise. Check if the DC link bus voltage was below the protective level when the
overvoltage alarm occurred.
 Implement noise control measures. For details, refer to the FRENIC-VG User's
Manual, "Appendix A."
 Connect a surge absorber to magnetic contactor's coils or other solenoids (if
any) causing noise.
(3) Connection of the external
braking resistor is wrong.
Check three sets of external braking resistor is being connected properly in DB1,
DB2, and DB3 terminal between DC link bus N bars.

Correct the connection.
(4) Inter- dynamic breaking unit
communications link error has
occurred.
By referring to the chapter of “ [9] Inter- dynamic breaking unit communications
link error “, and measures.
[ 3 ] DC Fuse blown
Problem The DC fuse connected to the Inverter P(+)-N(-) line connecting terminal (P(+), N(-)) blew.
Possible Causes What to Check and Suggested Measures
1) When attaching a DC fuse on input section of the dynamic breaking unit, connect b-contact of microswitch
provided for attachment to DC fuse to input terminals (DC1, DCF2) for detecting open fuse.
2) If the fuse has blown, the internal elements may be broken. NEVER turn the power ON to prevent the
secondary damage. Contact your Fuji Electric representative.
(1) The fuse blew due to
short-circuiting inside the
dynamic breaking unit.
Check whether there has been any excess surge or noise coming from outside.

Take measures against surges and noise.
 Ask your Fuji Electric representative to repair the dynamic breaking unit.
(2) The fuse blew due to ground
faults that have occurred at the
external braking resistor
connecting terminals.
Disconnect the wiring from the external braking resistor connecting terminals
[DB1], [DB2] and [DB3] and perform a Megger test for the inverter and the motor.
 Remove the grounded parts (including replacement of the wires, relay
terminals and motor).
 Ask your Fuji Electric representative to repair the dynamic breaking unit.
(3) The wiring of microswitch is
disconnected.
 Check for disconnection of cable by using tester, etc.
 Check for any loose wiring.(Also check for any loose terminal screw.)
[ 4 ] Memory error
Problem Error occurred in writing data to the memory in the dynamic breaking unit.
[ 5 ] CPU error
Problem A CPU error (e.g. erratic CPU operation) occurred.
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