In the event of an alarm, the adjustable frequency drive will have tripped. Alarms must be reset to restart operation once their cause has been rectified.

This may be done in four ways:

By using the [RESET] control button on the LCP control panel.

Via a digital input with the "Reset" function.

Via serial communication/optional serial communication bus.

By resetting automatically using the [Auto Reset] function, which is a default setting for the adjustable frequency drive, see par.14-20

Mode

VLT HVAC Drive Programming Guide, MG.11.Cx.yy

NOTE!

After a manual reset using the [RESET] button on the LCP, the [AUTO ON] button must be pressed to restart the motor.

If an alarm cannot be reset, the reason may be that its cause has not been rectified, or the alarm is trip-locked (see also table on following page).

Alarms that are trip-locked offer additional protection; this means that the line power supply must be switched off before the alarm can be reset. After

being switched back on, the adjustable frequency drive is no longer blocked and may be reset as described above, once the cause has been rectified.

Alarms that are not trip-locked can also be reset using the automatic reset function in par.14-20

If a warning and alarm is marked against a code in the table on the following page, this means that either a warning occurs before an alarm, or that it

can be specified whether it is a warning or an alarm that is to be displayed for a given fault.

This is possible, for instance, in par.1-90

on the adjustable frequency drive. Once the problem has been rectified, only the alarm continues flashing.

Motor Thermal Protection

. After an alarm or trip, the motor carries on coasting, and the alarm and warning flash

MG.11.C6.22 - VLT

is a registered Danfoss trademark

4 Troubleshooting

Reset Mode

(Warning: automatic wake-up is possible!)

Reset

4-1