Efficient Networks S120 manual Starting against applied brake, Emergency brake

Function modules 7.4 Extended brake control

When braking with a feedback signal (p1222), the inverted signal must be connected to the BICO input for the second (p1223) feedback signal. The response times of the brakes can be set in p1216 and p1217.

Note

If p1215 = 0 (no brake available) is set when a brake is present, the drive runs with applied brake. The can destroy the brake.

CAUTION

Brake control monitoring must only be activated for Booksize power units and Blocksize power units with Safe Brake Relay (p1278 = 0).

7.4.4Examples

Starting against applied brake

When the device is switched on, the setpoint is enabled immediately (if other enable signals are issued), even if the brake has not yet been released (p1152 = 1). The factory setting p1152 = r0899.15 must be disconnected here. The drive first generates torque against the applied brake. The brake is not released until the motor torque or motor current (p1220) has exceeded braking threshold 1 (p1221).

This configuration is used, for example, when the drive is connected to a belt that is under tension (loop accumulator in the steel industry).

Emergency brake

If emergency braking is required, electrical and mechanical braking is to take place simultaneously. This can be achieved if OFF3 is used as a tripping signal for emergency braking:

p1219[0] = r0898.2 (OFF3 to "apply brake immediately").

The OFF3 ramp (p1135) should be set to 0 seconds so that the converter does not work against the brakes. Regenerative energy may accumulate, and this must be either fed back into the supply system or converted into heat using a braking resistor.

This is often used, for example, in calendar stacks, cutting tools, running gears, and presses.

Operating brake for crane drives

For cranes with a manual control, it is important that the drive immediately response when the control lever is moved (master switch). The drive is powered-up using the on command (p0840) (the pulses are enabled). Speed setpoint (p1142) and speed controller (p0856) are inhibited. The motor is magnetized. The magnetization time generally applicable for three- phase motors (1-2 seconds) is therefore eliminated.

Now, there is only the brake opening time that is applicable as delay between moving the master switch and the motor rotating. If the master switch is moved (deflected), then there is a "setpoint enable from the control" (bit interconnected with p1142, p1229.2, p1224.0). The

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Function Manual, (FH1), 07/2007 Edition, 6SL3097-2AB00-0BP4