It’s worthwhile to remember that VFDs can offer benefits beyond energy savings, such as a soft start and the ability to ramp up and down, which might prolong the life of equipment or eliminate water hammer problems.
Another potential advantage is information. “There’s a lot of good diagnostic data that you can get out of the drive,” he says. With that data, facility managers can extract an estimate of power consumed to do some basic measurement and verification.
If the facility is running fault detection and diagnostics, that software can keep an eye on system performance. “If you have a VFD, you can start writing rules comparing power to speed, to delivered volume and start looking for anomalies automatically,” says Knight.
Knight notes that it’s is easier and less expensive than in the past to connect a VFD to a building automation system. While serial or Ethernet data connection ports used to be sold as an optional upgrade, today “everybody just gives you the port,” along with a choice of protocols, he says.
Facility managers considering VFD applications should check to see if there are incentives available for the project. “VFD incentives are common right now,” says Knight. But it’s important to be aware of the rules associated with the incentive program. Knight tells of one chief engineer who ordered new VFDs before going to the local utility to apply for an incentive. Unfortunately, because the engineer had already committed to buying the VFDs, the project didn’t qualify for the incentive.
Analyze VFD (Variable Frequency Drive) Retrofit Applications To Ensure Savings
VFDs Offer Benefits Beyond Energy Savings
