I/O Phase Loss Protection Selection - Mitsubishi Electric 800 Series Instruction Manual (Function

12.6

I/O phase loss protection selection

The output phase loss protection function, which stops the inverter output if one of the three phases (U, V, W) on the inverter's
output side (load side) is lost, can be disabled.
The input phase loss protective function on the inverter input side (R/L1, S/L2, T/L3) can be disabled.
Pr.
251 Output phase loss
H200 protection selection
872
Input phase loss
*1
protection selection
H201
*1 Available for the three-phase power input model only.
 Output phase loss protection selection (Pr.251)
• When Pr.251 is set to "0", output phase loss protection (E.LF) becomes invalid.
 Input phase loss protection selection (Pr.872)
• When Pr.872 = "1", Input phase loss (E.ILF) protection is activated if one of three phases is continuously lost for 1 second.
NOTE
• When several motors are connected, output phase loss cannot be detected even if the wiring to one motor loses phase.
• In the case of R/L1, S/L2 phase loss, the input phase loss protection does not operate, and the inverter output is shut off.
• If an input phase loss continues for a long time, the lives of converter section and capacitor of the inverter become shorter.
• If the load is light or during a stop, lost phase cannot be detected because detection is performed based on the fluctuation of
bus voltage. Large unbalanced phase-to-phase voltage of the three-phase power supply may also cause input phase loss
protection (E.ILF).
• Phase loss cannot be detected during regeneration load operation.
Parameters referred to
Pr.261 Power failure stop
288
12. (H) Protective Function Parameters
12.6 I/O phase loss protection selection
Name Initial value
1
1
selectionpage 455
Setting range
0 Output phase loss protection disabled
1 Output phase loss protection enabled
0 Input phase loss protection disabled
1 Input phase loss protection enabled
Description