7 motor speed monitoring, 8 encoder open-circuit monitoring, Motor speed monitoring – Lenze 8400 motec User Manual

Page 180: Encoder open-circuit monitoring, 5motor control (mctrl)

Motor control (MCTRL)

5.14

Monitoring

180

Lenze · 8400 motec · Reference manual · DMS 4.1 EN · 08/2013 · TD05

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5.14.7

Motor speed monitoring

This function extension is only available from version 04.00.00!

If the drive reaches the maximally permissible motor speed (

C00965

• The error response "Fault" occurs, i.e. the inverter is inhibited and the motor changes to torque-

free operation (coasts down).

• The error message "

OS2: Max. motor speed reached

" is entered into the logbook.

5.14.8

Encoder open-circuit monitoring

This function extension is available from version 02.00.00!

When does the open-circuit monitoring system respond?
The open-circuit monitoring will trigger if

• an open circuit occurs in the encoder cable.
• an extreme overload (e.g. blocked motor shaft) occurs during the start-up phase of the motor.
• highly dynamic reversion of the motor occurs.

Which measured values lead to an actuation of the open-circuit monitoring system?
The following measured values checked for plausibility lead to an actuation of the open-circuit

monitoring system:

1. If for a time > 0.2 s, the amount of deviation between the actual speed value and the speed

setpoint is higher than f = 40 Hz.

2. If for a time > 0.2 s, the detected actual speed value is f = 0 Hz or n = 0 rpm and the I

max

controller is active at the same time.

3. If for a time > 0.2 s, the injected frequency and the actual speed value have different signs and

the I

max

controller is active at the same time. This is usually the case if A/B tracks are mixed up.

Response to open circuit

• If the open-circuit monitoring is tripped: