What is the purpose of VFD in secondary Chilled water pump?

Secondary Pump in Chilled water system is responsible to pump the chilled water to load end i.e. AHU's. VFD's (Variable Frequency Drives) are usually employed to serve the purpose of feeding electrical power to pump motors as these provide a good control over speed of motor which in turn changes the GPM's (gallon per minutes) being supplied to load end. When demand is more the motor is run at full speed to have maximum GPM's whereas in case demand decreases the GPM's are reduced by reducing the motor speed through VFD. Accordingly we get two benefits from using VFD's i.e. to have control over GPM's as well as power conservation in case chilled water demand is low.

VFD Means Variable frequency drive. It is used in the pumps and fans on their motor to reduce speed when the demand is less. In this way we can save energy.

A Variable Frequency Drive (VFD) is a type of motor controller that drives an electric motor by varying the frequency and voltage supplied to the electric motor. Other names for a VFD are variable speed drive, adjustable speed drive, adjustable frequency drive, AC drive, micro drive, and inverter.

• The horsepower required of chiller pump to run a pump varies with the cube of its motor speed, resulting in large energy and cost savings when the motor speed is allowed to modulate in response to demand. Average annual energy savings.

• The life of building system equipment can be extended by gradually ramping up pumps and motors when increased capacity is required and by reducing the percentage of time pumps and motors work at full capacity. 

   

vfd in secondary (boaster pump)  or primary pump is to reduce rpm when the load decreases 

Variable frequency drive used to control pumps motor speed which affect the pressure and flow for the pump ( operating point 

This changes happened according to the heat load changes inside the building and the usage of the units 

VFD stand for variable frequency drive, a devise used to lower down the RPM of the chilled water pump, caused reduction in electricity consumption.

Its operating principle is quite simple when the design temperature of the space is achieved the sensors sensing the chilled water return temperature give the signal to two way valve to reduce the chilled water flow and in the same time these sensors send the signal to BMS system. BMS give the signal to VFD to lower the RPM of the chilled water pump.

VFD or Variable Frequency Drive is used to vary the speed of Motor as per demand.

VFD in secondary chilled water Pump is for controlling the discharge of flow in the Pump.

VFD's (Variable Frequency Drives) used to start the pump in lawer speed and to reduce speed when the demand is less. In this way we can save energy.

Variable Frequency Drives used for secondary chilled water pumps contols the flow of water by monitoring the system pressure. Pressure transducers (water pressure sensors) installed on chilled water line give necessary signal to VFD either to increase or decrease the motor speed to increase or decrease the water flow.

To maintain the required chilled water pressure in line by (Variable Frequency Drives).

As per required equipment or any other temperature.