HVAC & Chillers


In HVAC, efficiency is king. That is why variable frequency drives (VFDs) have become the standard control system in HVAC and large industrial chiller installations. VFDs offer precision speed control for motors driving pumps, chillers, fans, and compressors, yielding significant energy savings and lower operation costs. To further increase efficiency, many industrial HVAC applications are adopting permanent magnet (PM) motors.

In contrast to induction motors, permanent magnet motors have a constant magnetic field on the rotor, created by rare earth metals. Since the rotor creates its own magnetic field without electricity, this design drives efficiency up; however, it also makes permanent magnet motors much more susceptible to damage and stress due to voltage transients and high frequency harmonics. In order to minimize these potentially adverse conditions, CTM Sinewave Filters can be installed to virtually eliminate voltage transients and harmonic distortion, producing a near-ideal sinusoidal waveform which maximizes torque transmitted to the permanent magnet motor. Due to patented materials and unique geometry, CTM Sinewave Filters are the most energy efficient motor protection filters on the market.

For even greater efficiency gains, CTM specializes in liquid cooled systems, which allow better heat removal, yielding a smaller, more energy efficient solution than both natural convection and forced-air cooled systems. CTM is the industry leader in liquid cooled power quality solutions; we developed and shipped our first liquid cooled system in 2006, and have been perfecting the design and manufacturing process since then to produce the most reliable liquid cooled solution at the lowest cost.

While VFDs lead to increased energy efficiency, they also create a source of harmonic distortion, which can adversely affect all sensitive electronic equipment that shares the AC power supply. In order to protect sensitive equipment like computers, computer networks, telecommunications networks, and lighting, harmonic distortion must be mitigated wherever it is produced. CTM offers line/load reactors, which are an economic way to remove high frequency harmonic distortion throughout a system. Line/load reactors can be installed both in front of (line/grid side) and after (load/motor side) AC drives to protect sensitive equipment.

An additional detriment of harmonic distortion caused by variable frequency drives and other nonlinear loads is the effect this distortion has on the power grid. Due to the deleterious effects on the grid caused by excessive harmonics, most applications require compliance with IEEE 519, which is a standard that limits the amount of harmonic distortion allowed on a power system. While line/load reactors can be used to meet IEEE 519 requirements on systems with moderate distortion, for the ultimate in line (grid) side power quality filtering, CTM offers active front-end filters.