Honeywell ELECTRONIC REFRIGERATION CONTROL PCR-300 - Manual (Page 4)

¼ The controller must not be used as a safety cut-out device or excess
temperature limiter.
If the controller is used for purposes other than those stated
here, it shall not be considered to be use for the purpose
intended.
¼ Only connect sensors supplied with the unit. If a replacement sen-
sor is required, only use sensors of the same type (part no. H61007).
¼ The controller is not intended for use in vehicles because the
possible operating voltage ranges, interference level and
environmental operating conditions exceed the limits for which the
controller can be used.
¼ Please take the application limits into account
(see Technical Data, chapter 12).
3.2 Function
The PCR-300 is a microprocessor-controlled cold store control for
refrigeration and deepfreeze systems with a modular housing for
installation on 35 mm standard rails.
¼ Compressor control (dependent upon cold store
temperature) with delayed start-up.
¼ Evaporator fan control
ൎ Fan either in combination with compressor or
ൎ operating continuously or
ൎ switched via the evaporator thermostat.
¼ Defrost control limited thermostatically,
either for electrical heating or hot-gas defrosting
¼ Alarm output.
Defrosting is initiated via programmable intervals of time, max. 24/day.
The PCR-300 RC is provided with a real-time clock with a
back-up battery for defrost control. A maximum of six times per day
can be programmed.
4 Safety
4.1 Sources of danger
¼ Caution - Mains voltage.
¼ Never expose the unit to water or moisture. Risk of malfunction
and short circuit. Only use the unit when it is adjusted to normal
ambient temperature (+15 to +30 °C). Extreme changes in
temperature in combination with high atmospheric humidity may
lead to the formation of condensed water.
¼ Even if the control-circuit voltage is switched off, high voltage may
still be applied to the unit. For this reason, isolate all electric
circuits before starting any service work.
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