TECH EU-391 ZPID, User Manual

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VI.e) CH settings
CH settings enable the user to activate (or deactivate) voltage-free contact and buff er
sensor. If buff er sensor is active (Switching on buff er option selected), the pump is
enabled when CH temperature exceeds activation temperature and is higher than buff er
temperature by hysteresis value. Otherwise, the pump remains inactive.
The regulator has a voltage-free output which opens (or
closes) contact when CH temperature reaches the value
preset by the user. The setting range for this parameter
is 30÷750 C.
Voltage-free contact may be used to activate an external
heating device or initiate fi re-up process in a pellet-fi red
boiler.
NOTE
Voltage-free contact operation depends on CH
sensor readings unless buff er is switched on. If
buff er is switched on, the controller uses readings from the buff er sensor top
The user may also change CH pump activation temperature. It is the threshold temperature
value of pump activation. CH pump operates continuously until CH temperature drops
below the activation temperature minus CH hysteresis.
Additionally, CH hysteresis value may also be customised to suit individual needs. Hysteresis
is the diff erence between the temperature of CH pump activation and the temperature
when the CH pump is disabled (e.g. when activation temperature is 40ºC, hysteresis is
2ºC, the pump is disabled when CH temperature drops to 38ºC).
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User’s Manual