Mitsubishi Electric FR-A700 EC, Instruction Manual

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Operation setting at alarm occurrence Parameter
6 - 356
6.17.3 Input/output phase failure protection selection (Pr. 251, Pr. 872)
You can disable the output phase failure function that stops the inverter output if one of the
inverter output side (load side) three phases (U, V, W) opens.
The input phase failure protection selection of the inverter input side (R/L1, S/L2, T/L3) can be
made valid.
Output phase failure protection selection (Pr. 251)
When Pr. 251 is set to "0", output phase failure protection (E.LF) becomes invalid.
Input phase failure protection selection (Pr. 872)
When Pr. 872 is set to "1", input phase failure protection (E.ILF) is provided if a phase failure of
one phase among the three phases is detected for 1s continuously.
Pr.
No.
Name
Initial
Value
Setting
Range
Description Parameters referred to
Refer to
Section
251
Output phase failure
protection selection
1
0 Without output phase failure protection
261 Power failure stop
selection 6.16.2
1 With output phase failure protection
872
Input phase failure
protection selection
0
0 Without input phase failure protection
1 With input phase failure protection
NOTES If an input phase failure has occurred when Pr. 872 = 1 "Input phase failure protected" and a
value other than "0" (power failure stop function valid) is set in Pr. 261, input phase failure
protection (E.ILF) is not provided but power-failure deceleration is made.
When an input phase failure occurs in the R/L1 and S/L2 phases, input phase failure protec-
tion is not provided but the inverter output is shut off.
If an input phase failure continues for a long time during inverter operation, the converter
section and capacitor lives of the inverter will be shorter.