Several specific aspects of the compressor design render advanced performance, such as:
Optimization for varying pressure ratios and modesSmall scrolls VZH feature Intermediate Discharge Valves (IDVs). The IDVs inside the small platform are decisive to the system efficiency. The isentropic efficiency of a scroll compressor reaches a maximum at the built-in pressure ratio. When a compressor is operating below this built-in pressure ratio the efficiency drops due to overshoot: the discharge gas is at a pressure above the condensing pressure, the compressor over compresses the refrigerant.
The IDVs in the 4-7TR models partially avoid over-compression as they release the refrigerant before the built-in pressure ratio. This early release avoids efficiency losses due to overshoot and thus significantly enhance the energy efficiency for A/C systems at part-load conditions. The wide operating map makes the compressor suitable for very varied cooling and for heating applications, from 3 to 25kW of heating capacity.Permanent magnet motorThe efficiency comparison between asynchronous and synchronous motors shows instantaneously the great advantages obtained when using a permanent magnet motor technology with:
Wide capacity modulationThe inverter drive modulates the cooling capacity from 15% to 100% with a single compressor, which is very relevant for a variety of demanding applications where low part loads are needed.
Compact and reliable designThe 3 compressor displacements have the same dimensions and a compact footprint. This allows a cost effective and flexible design over a wide range of cooling capacities.
Furthermore, the IDVs significantly reduce the stress level on mechanical components at start-ups.
Stand out in the commercial HVAC and process cooling marketplace by boosting your unit performance and shortening development time with the Danfoss pre-qualified and manifoldable 4-26TR inverter packages.
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Optimization for varying pressure ratios and modes with Intermediate Discharge Valves (IDVs) and modes
Permanent magnet motor technology
Wide capacity modulation
Compact and reliable design
Danfoss Learning offers two courses on VZH inverter scrolls, giving you information about benefits and characteristics, and guidelines for installation and troubleshooting.
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