User manual

29
St
Grandezza controllata
R
REVERSE
rr rn rd
D
DIRECT
zona di non
intervento
==
St
Temperatura
R
rr
rd
rn/2 rn/2
rn
R
ENGLISH
ir33 +030220441 - rel. 2.5 - 16.06.10
Fig. 6.d
Fig. 6.e
6.11 Control with dead band
Control with dead band can be activated by using the aux1 or aux 2 output for the reverse step: H1 or H5=11. The set point ‘St’ is
in the centre of the dead band.
The parameter ‘rd’ represents the control di erential associated with the compressor, ‘rn’ the size of the dead band, ‘rr’ the di eren-
tial for reverse control associated with the aux1 or aux 2 output. The diagram in Figure 6.d shows control with dead band in the
case of direct operating mode (‘r3’=0 and 1).
The dead band is mainly used in direct operating mode. The diagram in Figure 6.e shows control with dead band in the case of
reverse operating mode (‘r3’=2).
The step associated with the aux1 or aux 2 output remains in reverse. The step associated with the compressor output passes from
direct to reverse.
Note:
1. the step associated with the aux1 or aux 2 output is only associated with the protection timer ‘c0’, while the step associated
with the compressor (in both direct and reverse) is associated with the timers ‘c0’ ‘c1’ ‘c2’ ‘c3’. As a result, the steps may be
active at the same time due to the protectors associated with the compressor step (minimum on time), as well as the unit
defrost status.
2. if the curtain switch function is enabled (‘A4’=7), the controller modi es the set point when the contact closes, adding or
subtracting the value of parameter ‘r4’; the new value is used for all functions relating to the set point (e.g. relative high and
low temperature alarms, dead band, etc.). When ‘r4’=3.0 (preset value) the set point is increased by 3 degrees compared to
the value used with the curtain open in direct mode, and decreased by 3 degrees in reverse mode. The rotation of the loads is
not envisaged in reverse operating mode (‘r3’=2). The following table de nes the status of the reverse output (aux1 or aux
2) in control with dead band.
Function active Reverse output in control with dead band
Normal direct or reverse-cycle control Normal operation
Remote o , from supervisor or keypad Reverse output deactivated
Defrost Normal operation
Continuous cycle Reverse output deactivated
Temperature alarm monitoring Normal operation
Evaporator fan control Normal operation
Power on Normal operation
Normally-open or normally-closed alarm output Normal operation
Auxiliary output Normal operation
Light output Normal operation
Second evaporator output Normal operation
Control output for pump down valve Normal operation
Condenser fan control output Normal operation
Second delayed compressor output Normal operation
Auxiliary output with switch o Normal operation
Light output with switch o Normal operation
No function associated with the AUX output Normal operation
Reverse output in control with dead band -
Second compressor step output Normal operation
Second compressor step output with rotation Normal operation
Door switch with compressor, fan o and light management Normal operation
Door switch with compressor o and light management Normal operation
Curtain switch with set point variation and light management Normal operation
Light sensor and light management Normal operation
Auxiliary output activation switch Normal operation
Door switch with compressor, fan o , no light management Normal operation
Door switch with compressor o , no light management Normal operation
Light activation from keypad or supervisor Normal operation
Auxiliary activation from keypad or supervisor Normal operation
Alarms See table of alarms and signals
Virtual control probe alarm Reverse output deactivated
Product probe alarm Normal operation
Defrost probe alarm Normal operation
Condenser probe alarm Normal operation
Antifreeze probe alarm Normal operation
Tab. 6.l