Dixell XRi77CX 5N6C0 cooling controller with PFM control of Variable speed compressors

The Dixell Model XRi77CX, 32 x 74 mm, is a microprocessor controller suitable for medium and low temperature cooling applications. It has 4 output relays to control compressor, fan, defrost (electric or hot gas) and light or alarm (configurable). The Dixell XRi77CX can control Variable speed compressors (For example, Embraco Fullmotion series). The control is based on a temperature probe and the output is the frequency value on the HotKey connector (VSC output). This output is controlled by PFM control (Pulse Frequency Modulation) with a pulse width of 50% and a frequency range of 30 to 200 Hz. A Dixell CAB/HK-VNEK interconnect cable is used for direct connection of an adequate compressor.

It is supplied with up to four PTC, NTC or Pt1000 inputs - one for temperature control, the other for evaporator defrost and fan control on the evaporator. One of the two digital inputs can be used as a third temperature input. The fourth input can be used to set the condenser temperature alarm or to display the condenser temperature. The controller has its own separate power supply from the power line, so that peripherals with different power supply or wiring can be used.

Optionally, it can include an RTC (Real Time Clock) that allows programming up to 6 defrost cycles, split between weekdays and days off. The "Day and Night" function allows two different desired temperatures to be set to save energy. A serial interface allows the device to be connected to a ModBUS RTU network, such as the Dixell X-Web family of monitoring networks. The HOT Key interface allows for quick and easy programming using the HOT Key or ProgToolKit.
The device is fully configurable with special parameters that can be easily entered using the keypad or ProgToolKit programming interface.