Hitachi SJ100 Electronic Thermal Overload Alarm Setting, Run, –FE, –FU, –FR, Func, Name, Mode, Edit, Code, (CE), (UL), (Jpn), Defaults, Description, SRW Display

5 20 60 Output frequency

Constant torque B_13 = 01

Reduced

torque

B_13 = 00

3–25

SJ100 Inverter

		“B” Function		Run		Defaults
Func.	Name /		Description	Mode	–FE	–FU	–FR	Units
				Edit
Code	SRW Display				(CE)	(UL)	(Jpn)
B_01	Selection of automatic		Select inverter restart method,	✘	00	00	00	—
	restart mode		four option codes:
			00... Alarm output after trip,
	IPS POWR	ALM
			no automatic restart
			01... Restart at 0Hz
			02... Resume operation after
			frequency matching
			03... Resume previous freq.
			after freq. matching, then
			decelerate to stop and display
			trip info.
B_02	Allowable under-		The amount of time a power	✘	1.0	1.0	1.0	sec.
	voltage power failure		input under-voltage can occur
	time		without tripping the power
			failure alarm. Range is 0.3 to
	IPS UVTIME 01.0s
			25 sec. If under-voltage exists
			longer than this time, the
			inverter trips, even if the restart
			mode is selected.
B_03	Retry wait time before		Time delay after under-voltage	✘	1.0	1.0	1.0	sec.
	motor restart		condition goes away, before
			the inverter runs motor again.
	IPS WAIT	001.0s
			Range is 0.3 to 100 seconds.

Electronic Thermal Overload Alarm Setting

The thermal overload detection protects the inverter and motor from overheating due to an excessive load. It uses a current/inverse time curve to determine the trip point.

First, use B_13 to select the torque characteristic that matches your load. This allows the inverter to utilize the best thermal overload characteristic for your application.

Torque

100%

80%

60%

0	Hz
120

The torque developed in a motor is directly proportional to the current in the windings,

which is also proportional to the heat generated (and temperature, over time). Therefore, you must set the thermal overload threshold in terms of current (amperes) for parameter B_12. The range is 50% to 120% of the rated current for each inverter model. If the current exceeds the level you specify, the inverter will trip and log an event (error E05) in the history table. The inverter turns the motor output OFF when tripped. Separate settings are available for the second motor (if applicable) as shown in the following table.