Protective functions – MITSUBISHI ELECTRIC FR-A500L User Manual
Page 37
PROTECTIVE FUNCTIONS
26
Operation
Panel
Display
(FR-DU04)
Parameter
Unit
(FR-PU04)
Name
Description
E.CTE
Operation panel power short
circuit
When the operation panel power (P5S of the PU connector) is shorted,
this function shuts off the power output. At this time, the operation panel
(parameter unit) cannot be used and RS-485 communication from the PU
connector cannot be made. To reset, enter the RES signal or switch
power off, then on again.
Brake resistor overheat
protection
Inverters of 7.5K or less contains a brake resistor. When the regenerative
brake duty from the motor has reached 85% of the specified value, pre-
alarm (RB indication) occurs. If the specified value is exceeded, the brake
circuit operation is stopped temporarily to protect the brake resistor from
overheating. (If the brake is operated in this state, regenerative
overvoltage shut-off will occur.) When the brake resistor has cooled, the
brake operation is resumed.
E.MB1 to
MB7
Brake sequence error
This function stops the inverter output if a sequence error occurs during
the use of the brake sequence function (Pr. 278 to Pr. 285).
E.14
E.14
DC fuse blown
The inverter output will stop if the DC fuse blows.
E.15
E.15
Main circuit error
Brake unit cooling fin overheat, control board ambient temperature error,
output overcurrent, cooling fan power supply error, capacitor overcurrent,
cooling fin overheat, gate power supply error.
Refer to the next page (page 27) for details.
Note: 1. If Pr. 195 (A, B, C terminal function selection) is as set in the factory.
2. The terminals used must be allocated using Pr. 190 to Pr. 195.
3. External thermal relay operation is only activated when "OH" is set in any of Pr. 180 to Pr. 186
(input terminal function selection).
4. Indicates that the stall prevention operation level has been set to 150% (factory setting). If this
value is changed, stall prevention is operated at the new value.
5. Resetting method
When the protective function is activated and the inverter stops its output (the motor is coasted to
a stop), the inverter is kept stopped. Unless reset, the inverter cannot restart. To reset the inverter,
use any of the following methods: switch power off once, then on again; short reset terminal RES-
SD for more than 0.1 seconds, then open; press the [RESET] key of the parameter unit (use the
help function of the parameter unit). If RES-SD is kept shorted, the operation panel will show "Err."
or the parameter unit will show that the inverter is being reset.