Output Phase Failure Protection Selection (Pr. 251) - Mitsubishi Electric FR-E520 Instruction Manual

When the Pr. 250 value is 8888, the functions of terminals STF and STR change as
shown below:
STF = start signal, STR = rotation direction signal
STF STR
OFF OFF
OFF ON
ON OFF
ON ON
When the Pr. 250 value is any of 1000 to 1100s, the functions of terminals STF and STR
are the same as when the Pr. 250 value is 8888.
Also, for the stopping method used when the start signal switches off, the output is shut
off (the motor coasts to a stop) after the period set in Pr. 250 (i.e. 1000s) have elapsed.
Note: 1. The RUN signal switches off when the output stops.
2. When the start signal is switched on again during motor coasting, the motor
starts at 0Hz.
3. When the Pr. 250 value is 0, the output is shut off within the shortest time.

4.2.49 Output phase failure protection selection (Pr. 251)

Pr. 251 "Output phase failure protection selection"
You can make invalid the output phase failure protection (E.LF) function which stops the
inverter output if one of the three phases (U, V, W) on the inverter's output side (load
side) becomes open.
Choose "without output phase failure protection" when the motor capacity is smaller
than the inverter capacity (when the output current is less than approximately 25% of
the rated inverter current value as a guideline), since performing operation in such a
case may activate output phase failure protection.
Parameter Setting
Number Range
251 0, 1
# # # # Refer to Pr. 117
Pr. 342
Inverter Operating Status
Stop
Forward rotation
Reverse rotation
Minimum
Factory
Setting
Setting
Increments
1
168
0: Without output phase failure
protection
1
1: With output phase failure
protection
PARAMETERS
Description