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Sleep mode
When the requirements of an HVAC system are examined over a time period, the plant often displays a varied load profile. There may even be periods when there is no real need for the operation of a HVAC system, or time periods where the requirement to a fan or a pump is so low that actual operation is will not impact the system.

To save energy during these periods, the "Sleep Mode" feature has been introduced to the VLT 6000 HVAC drive.

The VLT 6000 HVAC drive is programmed to a sleep frequency usually equal to the minimum motor speed desired by the user. When the motor has been running at this frequency for a specific (programmable) time period, the drive enters "sleep mode" and the power to the motor will be switched off.

When "sleep mode" is in operation, the drive will continue monitoring the system. When the systems setpoint is no longer satisfied, power to the motor will be turned on again.

The sleep and wake inputs to the drive are both frequencies to enable this function to work in both open loop and closed loop modes.

For further information please contact your local Danfoss Company