Screw compressor with direct drive and frequency control Frick by Johnson Controls

Vyper Variable Speed Drive

The Frick Vyper Variable Speed Drive for screw compressors offers the refrigeration industry superb system performance, enhanced energy savings, and reduced maintenance costs.
The Vyper VSD provides fast, precise, and wide-ranging response to rapidly changing loads. The liquid-cooled, NEMA 4 rated cabinet provides protection from ammonia vapors while the Quantum™LX control panel provides a user-friendly interface for ease of operation. The drive is available in 150, 305, 435, 687 and 957HP models and can be mounted either directly on the compressor package or remotely.

The package mount method provides easy on site installation of new equipment while the remote mounting method offers an easy solution to retrofitting a constant speed drive with the Vyper VSD for energy cost savings and or enhanced performance.

Replacement with a conventional screw compressor with mechanical capacity control (slide valve) can not provide the rapid response to load fluctuations, but when the Frick screw compressor with variable Vi control is driven by the Vyper VSD, rapid response is no longer a concern.

The Vyper is capable of starting and coming up to full speed in 10 seconds. Capacity control with speed, as low as 20% (720RPM) means the slide valve should never move for capacity control. This results in virtually no wear to the slide valve. Also, since the slide valve stays loaded, economizers are always at full capacity and Vi control which fluctuates as the slide is unloaded stays Ideal through the speed range using the Vyper VSD.

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