Commercial air-conditioners and chillers

In commercial roof top units (RTUs) and chillers, different compressor types such as scroll, piston, screw and centrifugal compressors are used.
Our range of soft starters is suited for all types of induction motor compressors. RSBD and RSBT soft starters are designed specifically for scroll compressors. Both soft starters do not require any user parametrization as they work on a self-learning control that optimizes the start current reduction at every compressor start.
For piston and screw compressors, RSGD and RSGT offer more flexibility in terms of user adjustments.

Heat pumps are required to reach higher seasonal efficiencies to be placed on the market. The need to be highly efficient also in partial load operation requires a new technology of compressors that can work at low and high speeds. Both permanent magnet (PMAC) and brushless DC (BLDC) compressors are now commonly used in heat pumps.
RVPM is our variable frequency drive (VFD) that can work with 1-phase input and 3-phase input PM, BLDC as well as induction motor compressors.

The speed of AC condenser fans in RTUs and chillers can be varied through the principle of phase angle control. By varying the output voltage proportionally to an analogue input voltage a solid state proportional controller such as RGC1P and RCG3P series can regulate the speed of low starting torque and low inertia induction motor fans resulting in lower power consumption. Several condenser fans can be grouped together and controlled by a single proportional controller.

The starting point at improving energy efficiency is that of monitoring the energy flows. HVAC systems are big consumers of electricity in any sizeable building. Our solutions of energy meters cater for different use cases and installation requirements.
DIN-rail mount energy meters are the preferred choice with OEMs due to the easy integration within electrical panels. They come with both direct connection inputs as well as current transformer (CT) input versions.
For enhanced power metering, WM series of power analyzers offers extensive measuring capabilities and is equipped with different communication protocols (including BACnet) for easier integrations to BEMS.

Reverse operation of a compressor quickly causes it to fail and shut the whole equipment down. In addition 3-phase voltage quality impacts the chiller lifetime and must be monitored. Our DPA51 and DPB51 three-phase relays are the de facto standard in the market for reliability, size and performance. It is also important to be sure that some of the loads on the systems, such as distribution pumps, are running when required.
Our EISH, DIA53 and DIB01 ON/OFF relays monitor the load current to know if the load is operating, reducing downtime in case of fault with an early warning.

Switch mode power supplies are a crucial part in powering up most of the critical components within the electrical panel of any HVAC solution.
Our SPDC series of DIN-rail mount power supplies offers a number of unique features such as ultra-slim design, integrated PFC and efficiencies up to 96%.