User manual

21
ENGLISH
ir33 +030220441 - rel. 2.5 - 16.06.10
6.4 Auxiliary output management
The auxiliary output can be controlled by a number of sources: button, supervisor, digital input, and time band. The AUX is
switched on and o in the following events:
Aux Action
Button pressing the button
Supervisor variation in value from the supervisor
Digital input change in the status of the contact (opening/closing)
Time band according to day, hour, minutes for switching on/o
Tab. 6.e
Therefore, if the digital inputs are stable, the AUX output can always be activated and de-activated from the keypad or the supervisor.
The timed light or AUX on/o events (parameters tON and tOFF, depending on parameter H8) are also active when the unit is o .
Note: the anti-sweat heater function, when the control is powered up or switched on, keeps the auxiliary output o until the
control temperature is below the set value. The AUX output is activated when the event occurs.
6.5 Light management
The light can be controlled by a number of sources: button, supervisor, door switch, curtain switch, light sensor and time band.
The light is switched on and o in the following events:
Light Action
Button pressing the button
Supervisor variation in value from the supervisor
Door switch change in the status of the contact (opening/closing)
Curtain switch change in the status of the contact (opening/closing)
Light sensor on detecting light or darkness
Time band according to day, hour, minutes for switching on/o
Tab. 6.f
When the digital inputs (selected as door or curtain switches) are stable, the light can always be switched on or o from the
keypad or the supervisor. The door switch features two di erent algorithms for switching the light on/o :
• the status of the light is not a ected, and acts only on the compressor and fans;
• timed light or AUX on/o events (depending on parameter H8) are also active when the unit is o .
Note: the anti-sweat heater function, when the control is powered up or switched on, keeps the light output o until the control
temperature is below the set value. The light output is activated when the event occurs.
6.6 Defrost
The parameter dC establishes the measurement unit for the times set by the parameters dI (defrost interval) and dP1, dP2 (maxi-
mum defrost duration). If the auxiliary relay is selected as the auxiliary evaporator defrost output (H1), the defrost is performed
at the same time on both evaporators. The parameter d/1 displays the defrost probe set for the main evaporator (the  rst probe
assigned as a defrost probe); while parameter d/2 displays the defrost probe set for the secondary evaporator (the second probe
assigned as a defrost probe). If no probes have been assigned to the defrost function, the defrost will end by timeout, after the
periods dt1 and dt2.
6.6.1 Defrost events
The following events activate the defrost function:
Event Implementation Update dI
Interval between defrosts dI expired Depending on enabling status At the expiry of the interval
Expiry of RTC trigger Depending on enabling status -------
Compressor running time Depending on enabling status When the defrost starts
Interval between defrosts dI expired with skip defrost
algorithm
Depending on enabling status At the expiry of the interval
At start-up Depending on enabling status At start-up + d5
Digital input Depending on enabling status When the defrost starts
Supervisor Always --------
Keypad Always --------
Tab. 6.g
Implementation of defrost depending on enabling status:
If a digital input is con gured to enable the defrost, the defrost is performed when such input is in the enabling status, otherwise
it stays pending.
Important: the defrost requested from the keypad or by the supervisor is always performed, even when there is a delayed defrost
request from external digital input or if there is a defrost enabling input (in non-enabled or delayed status). If parameter r3 is set
to 1 (Direct) or 2 (Reverse), the defrost is never performed.
6.6.2 Defrost request status
This status exists when one of the events that activates the defrost is present, but defrost cannot be started and, therefore, is put
on hold for the following reasons:
• compressor and fans start-up delay (c0), as these delay the activation of the compressor;
• compressor protection times (c1, c2, c3), as these delay the activation of the compressor;
• low pressure alarm (only with hot gas defrost), as this delays the activation of the compressor;
• continuous cycle running;
• pump down procedure running, as this delays the activation of the compressor;
• defrost delay at start-up (d5);
• defrost delay from digital input con gured as defrost start or enable (d5);
• enable defrost (A4, A5, A9);