PS D370 ... 840 for 690V 

tallations of softstarters type PSD in industrial network: 

In softstarters PSD thyristors and microprocessors are used that can cause emission during operation. This emission can be reduced by using a by-pass contactor, that ensures that the system fulfils the compatibility requirement. Another advantage by using a by--pass contactor is that the total powerloss is reduced, and thus it is not needed to have extra fans for cooling if the softstarter is enclosed. 

  By-pass contactor: When a by-pass contactor is used the softstarter is by-passed at continues operation, The by-pass contactor is connected in parallel to the softstarter that is only active during start and stop of the motor. The operation is simplified if the built in  signal relay K5 (top of ramp / TOR) is used to control the by-pass contactor. The by-pass contactor is automatically in operation after completed start and will remain so during continuous operation. The Softstarter can still be in active status but no current will pass through it, instead all current will pass through the by-pass contactor. For connection of the by-pass contactor, please see section 2. 

  Function PF (Energy saving at low motor load): Can not be activated during operation with a by?pass contactor included. 

  Earthing: The Softstarter has to be connected to earth. 

Installation of Softstarters type PSD in public network: 

In softstarters PSD thyristors and microprocessors are used that can cause emission/disturbances during operation. In public network the requirements only allow for low emission levels. In order to fulfil this requirement some actions must be taken. 

Mounted in any metal enclosure with a by-pass contactor and using screened cables outside the enclosure the system fulfils the compatibility requirement. Another advantage by using a by-pass contactor is that the total powerloss is reduced, and thus it is not needed to have extra fans for cooling. Below you will find closer description of each action;