Mitsubishi Electric FR-A520-0.4K-NA Instruction Manual page 189

Operation
Parameter
Panel
Unit
Display
(FR-PU04)
(FR-DU04)
Brake resistor overheat
 
protection
E.MB1 to

Brake sequence error
MB7

Err Error
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 second, 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.
Name
Inverters of 7.5K or less contain 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.
This function stops the inverter output if a sequence error occurs during
the use of the brake sequence function (Pr. 278 to Pr. 285).
The inverter output is stopped if a malfunction occurs in the built-in CPU.
176
PROTECTIVE FUNCTIONS
Description