Hitachi SJ700-2 Disabling the brake control function, Enabling the brake control function

Chapter 4 Explanation of Functions

When using the brake control function, assign the following signal functions to intelligent input and intelligent output terminals as needed.

(1)To input a signal indicating that the brake is released from the external brake to the inverter, assign the braking confirmation signal (44: BOK) to one of the terminal [1] to [8] functions (C001 to C008).

(2)Assign the brake release signal (19: BRK), which is a brake-releasing command, to one of the intelligent output terminals [11] to [15] (C021 to C025). To output a signal when braking is abnormal, assign the brake error signal (20: BER) to an intelligent output terminal.

When using the brake control function, you are recommended to select the sensorless vector control (A044 = 03) 0Hz-range sensorless vector control (A044 = 04) or V2 (A044=05)as the V/F characteristic curve selection that ensures a high starting torque. (See Section 4.2.18.)

Settings required for the brake control function

Item	Function code	Data or range of data	Description
Brake Control Enable	b120	00	Disabling the brake control function
		01	Enabling the brake control function
			Time to wait after the output frequency
Brake Wait Time for	b121	0.00 to 5.00 (s)	has reached the release frequency until
Release			the output current reaches the release
			current
Brake Wait Time for			Mechanical delay after the release
	b122	0.00 to 5.00 (s)	signal has been output until the brake is
Acceleration
			released
Brake Wait Time for			Mechanical delay after the release
	b123	0.00 to 5.00 (s)	signal has been turned off until the brake
Stopping
			is applied
			Wait time longer than the delay after the
Brake Wait Time for	b124	0.00 to 5.00 (s)	release signal output until the release
Confirmation			completion signal output from the brake
			is input to the inverter
Brake Release Frequency	b125	0.00 to 99.99 or 100.0 to	Frequency at which to output the brake
Setting		400.0 (Hz)	release signal (*1)
Brake Release Current	b126	"0 x rated current" to	Frequency at which to permit brake
Setting		"2.0x rated current" (%)	releasing (*2)
Braking frequency	b127	0.00 to 99.99 or 100.0 to	Frequency at which to apply the brake
		400.0 (Hz)	for stopping the motor (*1)

*1 Specify a frequency higher than the start frequency (b082).

*2 Note that setting a low current may not ensure sufficient torque at brake releasing.

The inverter will trip with the braking error signal (BER) (E36: brake error) output in one of the following cases:

1)The inverter output current brake remains below the brake release current, even after the release wait time (b121).

2)During acceleration, the braking confirmation signal (BOK) is not turned on within the braking wait time (b124). During deceleration, the braking confirmation signal (BOK) is not turned off within the braking wait time (b124). Otherwise, the braking confirmation signal is turned off although the brake release signal is output.

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