Hitachi L2002 Automatic Restart Mode

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L2002 Inverter

“B” Group: Fine Tuning Functions

The “B” Group of functions and parameters adjust some of the more subtle but useful aspects of motor control and system configuration.

Automatic Restart Mode

The restart mode determines how the inverter will resume operation after a fault causes a trip event. The four options provide advantages for various situations. Frequency matching allows the inverter to read the motor speed by virtue of its residual magnetic flux and restart the output at the corresponding frequency. The inverter can attempt a restart a certain number of times depending on the particular trip event:

•Over-current trip, restart up to 3 times

•Over-voltage trip, restart up to 3 times

•Under-voltage trip, restart up to 16 times

When the inverter reaches the maximum number of restarts (3 or 16), you must power cycle the inverter to reset its operation.

Other parameters specify the allowable under-voltage level and the delay time before restarting. The proper settings depend on the typical fault conditions for your applica- tion, the necessity of restarting the process in unattended situations, and whether restarting is always safe.

Power failure < allowable power fail					Power failure > allowable power fail
time (B002), inverter resumes					time (B002), inverter trips
Input					Input
power					power
0					0
Inverter					Inverter
output					output
0					0
Motor			free-running		Motor			free-running
speed					speed
0					0
		Power fail		t		Power fail			t
Allowable								Allowable
power fail time	B002					B002	power fail time
Retry wait time
		B003

Parameters Drive Configuring