Mitsumi electronic FR-F520-0.75K, 55K Motor current is large, Speed does not increase

PROTECTIVE FUNCTIONS

5.2.5 Motor current is large

Check that the load is not too heavy.

Check that the torque boost (Pr. 0, Pr. 46) setting is not too large.

Check that the set value of the load pattern selection (Pr. 14) is proper for the application.

5.2.6 Speed does not increase

Check that the maximum frequency (Pr. 1) setting is correct.

Check that the load is not too heavy. (In agitators, etc., load may become heavy in winter.)

Check that the torque boost (Pr. 0, Pr. 46) setting is not too large to activate the stall prevention function.

Check that the brake resistor is not connected to terminals P<+>-P1 accidentally.

5.2.7 Speed varies during operation

1) Inspection of load

Check that the load is not varying.

2) Inspection of input signal

Check that the frequency setting signal is not varying.

Check that the frequency setting signal is not affected by induced noise.

Check that a malfunction does not occur due to an undesirable current when the transistor output unit is connected, for example. (Refer to page 18.)

5.2.8 Operation mode is not changed properly

If the operation mode is not changed properly, check the following:
1.	External input signal		........ Check that the STF or STR signal is off.
			When it is on, the operation mode cannot be changed.
2.	Parameter setting	........... Check the Pr. 79 setting.
			When the setting of Pr. 79 "operation mode selection" is "0" (factory
			setting), switching input power on places the inverter in the external
			operation mode. Press the operation panel's MODE key two times and

press the key (press the PU key for the parameter unit (FR-PU04)). This changes the external operation mode into the PU operation mode. For any other setting (0 to 4, 6 to 8), the operation mode is limited according to the setting.

(For the detail of Pr.79, refer to 105 page)

5.2.9 Operation panel (FR-DU04) display is not provided

Make sure that the operation panel is connected securely with the inverter.

5.2.10 POWER lamp is not lit

Make sure that the wiring and installation are correct.

5.2.11 Parameter write cannot be performed

Check that operation is not being performed (signal STF or STR is not ON). Check that the SET key (WRITE key) is pressed for longer than 1.5 seconds.

Check that you are not attempting to make parameter setting outside the setting range. Check that you are not attempting to make parameter setting in the external operation mode. Check the setting of Pr. 77 "parameter write inhibit selection".

175