Using the line contactor

Proceed as follows:

  1. Always place the line contactor before the line filter (if present).
  2. Use at least one contactor of utilization category AC‑3 (EN 60947-4-1) as a line contactor.
  3. NOTICE! Failing to observe the minimum switch-off time of the line contactor can cause material damage. Irreparable damage to the inverter or unforeseen malfunctions. After switching off the voltage supply, keep it switched off for at least 10 s.
    • Do not switch on the voltage supply of 3-phase devices more frequently than once every 60 seconds.
    • Do not switch on the voltage supply of 1-phase devices more frequently than once every 120 seconds.
  4. Do not use the line contactor for jog mode, but only for switching the device on and off.

The following table provides an overview of when a line contactor is required. Observe the information on the necessary protective measures for the braking resistor used in the Product manual > chapter Protecting the braking resistor against thermal overload.

Inverter

Braking resistor

Protective element/
preventive measure

Line contactor
required

Size
0S, 0L, 3

No BW..

–

No

BW.. Flat design

–

No

BW.. as PTC

–

No

BW..

External overload relay

Yes

BW..-T

Temperature contact evaluation

Yes

From size 4

No BW..

–

No

BW.. Flat design

–

No

BW.. as PTC

–

No

BW..

External overload relay

No

BW..-T

Temperature contact evaluation

No

      If a braking resistor is connected to the inverter from size 4 without using a line contactor, an external DC 24 V voltage supply must be provided on the inverter.