OL1 (Inverter overloaded):

+ Rapid acceleration is operated.
+ DC braking rate is too high.
+ V/f parameter is improperly set.
+ Running motor is started during momentary power failure status or so.
+ Load is too heavy.
    Countermeasures:
+ Extend acceleration time (#ACC).
+ Decrease values of DC injection braking current (#51) and DC injection braking time (#52).
+ Check V/f parameter.
+ Use F301 (Auto-restart) and F302 (Regenerative power ride-through control).
+ Raise rating of the inverter.

OL2 (Motor overloaded):
+ V/f parameter is improperly set.
+ Motor is locked.
+ Continuous operation in low speed range.
+ Motor is operated with overload.
    Countermeasures:
+ Check V/f parameter.
+ Check loading unit.
+ Reset (#56) properly to motor's overload reduction start-up frequency.

OLr (Dynamic braking resistor overload):
+ Rapid deceleration is operated.
+ Dynamic braking rate is too high.
    Countermeasures:
+ Extend deceleration time (#dEC).
+ Increase capacity (wattage) of dynamic braking resistor and reset the PBR capacity parameter (#309).
+ Increase the setting value of (#526).

OH (Overheat):
+ Cooling fan is not actuated.
+ Ambient temperature is too high.
+ Vent of cooling fan is shut.
+ Some heat generating matter is located nearby.
+ Internal thermistor of unit is disconnected.
    Countermeasures:
+ After cooling down inverter, reset it from failure and try to restart it.
+ If cooling fan does not work in operation, it needs replacement.
+ Secure spaces in the periphery of the inverter.
+ Don’t locate any heat generating thing near the inverter.
+ Make a service call.

E (Emergency stop!!):
+ Inverter is stopped by panel operation during automatic or remote operation.
    Countermeasures:
+ Reset the inverter.

EEP1 (EEPROM error):
+ Error occurs during writing data.
    Countermeasures:
+ Again turn on the inverter. If it is not reset, make a service call.

EEP2/EEP3 (Initial read-error):
+ Something abnormal in internal data.
    Countermeasures:
+ Make a service call.

Err2 (Main RAM fault):
+ Something abnormal in control RAM.
    Countermeasures:
+ Make a service call.

Err3 (Main ROM fault):
+ Something abnormal in control ROM.
    Countermeasures:
+ Make a service call.

Err4 (CPU fault):
+ Something abnormal in control CPU.
    Countermeasures:
+ Make a service call.

Err5 (Interruption communication fault):
+ Something abnormal occurred during communication operation.
    Countermeasures:
+ Check communication units and their connections.

Err6 (Gate array fault):
+ Main gate array is abnormal.
    Countermeasures:
+ Make a service call.

Err7 (Output current detector error):
+ Main output current detector is abnormal.
    Countermeasures:
+ Make a service call.

Err8 (Optional unit fault):
+ Something abnormal occurred in some optional unit (including additional communication optional add-on cassettes).
    Countermeasures:
+ Check connection of optional board(s).
+ Refer to instructions of options concerned.

Err9 (Flush memory fault):
+ Something abnormal in flush memory.
    Countermeasures:
+ Make a service call.

UC (Low-current operation):
+ Output current declined to the low-current detection level during operation.
    Countermeasures:
+ Check to see if low-current detection level is set properly to the system or not (#5 and #1).
+ If low-current detection level is properly set, make a service call.

+ Toshiba VFD P7 User Manual >

+ Toshiba VFD P7 >

+ Toshiba P7 Fault index >

+ Toshiba P7 Fault codes 1 >

+ Toshiba P7 Fault codes 2 >

+ Toshiba P7 Fault codes 3 >

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