Carel: The First Speed Drive For Dc Compressors With Integrated And Certified Protection

CAREL has introduced PSD2, the new Power+ family series of speed drives for DC compressors.

PSD2 comes with a distinctive and unique feature on the market: integrated and certified compressor protection to guarantee unit safety. This means the various external protection devices are no longer needed, with a considerable economic advantage in terms of total unit cost. With PSD2, thermal overload devices (Klixons), circuit breakers (thermal over-current relays) and electromechanical devices (contactors, if used exclusively for compressor protection or activation in the event of overpressure) are no longer required: the benefits are cost savings, less space requirements and simplified wiring.

Safety and compliance

The PSD2 series speed drives guarantee compliance with IEC and UL 60335-1, where applicable, as well as IEC and UL 60730-1, thanks to integrated compressor protection. Compliance with these standards, as well as guaranteeing safety and protection for users, is a legal requirement for all manufacturers.

In addition, the “safe torque off” (STO) input is certified according to EN13849-1 for use with safety devices, such as high pressure switches.

Compliance with these standards simplifies the procedure for certification of the unit and avoids the need to install and calibrate the various additional protection devices.

Thanks to certified class B software, PSD2 provides much higher compressor protection than traditional systems. The use of redundancy measures and plausibility checks prevents dangerous situations arising for the unit, and in the event of a major failure, can limit it, both at a software level and hardware level. Class B software, as defined by the relevant standard, is a control function that can carry out an automatic action to prevent hazards or failures and to always maintain a predefined level of safety in order to safeguard the product and consequently people or objects that come into contact with it.

Applications

-      refrigerated showcases in supermarkets

-      HVAC

-      heat pumps