Beskrivning
Models XW270K and XW271K are microprocessor based controllers suitable for applications on medium or low temperature refrigerating units. They must be connected by means of a two-wire cable ( 1mm) at a distance of up to 30 meters to the keyboards T820 or T821. They are provided with six relay outputs to control compressor, defrost – which can be either electrical or hot gas – the evaporator fans, the lights, the alarm and an auxiliary output. In XW271L the auxiliary output is configured as anti-condensing heater.
They are also provided with three NTC probe inputs, one for temperature control,
one to control the defrost end temperature of the evaporator and the third, optional,
for the display. There are two digital inputs (free contact) for the door switch and
configurable by parameter.
The standard TTL output allows the user to connect, by means of a TTL/RS485
external module, a ModBUS-RTU compatible monitoring system and to programme
the parameter list with the “Hot Key”. An optional output for RS485 direct is
available.
