As in the previous comments on using inverters on centrifugal pumps and fans in AHU’s and water systems to save energy, then to give better and even more accurate control on energy savings using inverters, then using P.I.D control (proportional integral derivative) in everyday language sensors, fitted along with the inverter, will give better control.
Again to give an example using the driving of a car as an analogy, P.I.D control can be compared with the cruise control on a car.
As you are driving along a motorway for example, you set the cruise control at say 60mph and take your foot of the accelerator sensors in the vehicles engine will then detect when more power is required for example going uphill, it will automatically increase the engine speed to maintain 60mph.
The opposite applies when going downhill and power to the engine is decreased. So with inverters they have the parameters within the inverter itself, to set a speed of air or water flow that is required by the use of pressure sensors, velocity sensors heat sensors etc. These can be set whenever the user requires. The inverter will speed up or slow down the motor to achieve the parameters set on install.
The best example I can give is when new filters are fitted to an AHU, the air flow is increased due to the filter being clean, however if P.I.D control is not fitted then as the filter clogs up over its life cycle with dust etc. Then obviously the air flow will decrease until the new filters are fitted.
However if a pressure sensor is fitted to the other side of the filter and the signal sends back to the inverter as the filter clogs up and the air flow decreases below the parameter set and required by the end user, then the inverter will either speed up or slow down to maintain that parameter or air flow set, exactly the same as the cruise control on your car!
If you have any queries regarding PID Control Sensors on Inverter Drives then contact our engineers on 0115 944 1036 or email [email protected] we are here to help!