Operating instructions
cod. 1592011000
1592011000 XC706M GB 31-08-2001
rel. 1.0
Pa. 14 / 23
NOTE
1.
The regulation algorithm turn on a load when the pressure coming from the “lower out
band” reaches the set point.
2.
The regulation algorithm turns off a load when the pressure coming from the “upper out
band” reaches the set point.
Ex. Dead band control, compressors with same capacities, 1 step for each compressor.
In this example:
CPnu = 3 number of compressors
CtyP = 1 homogeneous compressors;
CPSt = 1 one step for each compressor;
rty = db dead band regulation
Sty = rot rotation
FdLy = no
“don” delay not enabled at first calling after an equilibrium
condition.
dLF = no “doF” delay not enabled at first calling after an equilibrium condition.
S e t
&
Stato dei
compressori
7HPSR
Pressione
2Q
& 2Q
& 2Q
]RQD LQVHULPHQWR FRPSUHVVRUL
]RQD QHXWUD
don
doF
don
doF
GR)
GRQ
Andam ento
ritardi
7HPSR
7HPSR
S e t + (P b d/2 )
S e t - (P b d /2 )
]RQD GLVLQVHULPHQWR FRPSUHVVRUL
6.2 Proportional
Band
The regulation band (Pbd) is divided into as many parts as there are stages according to the
following formula:
# step = CPnu x CPSt. (number of compr. x num. of steps).
The numbers of stages switched ON is proportional to the value of the input signal: when this
distances itself from the target set point and enters the various bands, the compressors are
switched ON, to be then turned OFF when the signal brings near the set point.
In this way if the pressure is greater than regulation band, all the compressors are on, if the
pressure (temperature) is lower than the regulation band all the compressors are off.
Naturally also for this regulations all the delays (don and doF) safety times (onon, oFon and
donF) are valid.
