User manual
1592022700 User manual iCHILL 200CX  Rel. 1.0 22/04/2009 
Pg.38/114
20.4  PART WINDING 
This  algorithm  allows  to  reduce  the  start-up  current  when  using hermetic  or semi-hermetic  compressors  or  medium  –  big screw 
compressors. 
Each compressor needs two relay outputs: 
•  One is the PW motor coil 1 of the compressor; 
•  One is the PW motor coil 2 of the compressor 
The time delay between the two outputs is determined by CO11 expressed in decimal of second. 
The maximum number of relay outputs is 4 this means 2 compressors with Part Winding start-up. 
First is turned on the PW motor coil 1 of the compressor 1 (relay K1 of fig2), after the CO11 delay it is turned on the second motor coil of 
the same compressor (relay K2 of fig2). 
To turn off the compressor the two relay outputs are both turned off at the same time. 
Fig 2  
20.5  PART WINDING START- UP OF COMPRESSORS OR CAPACITY COMPRESSORS 
If  one  or  more capacity compressors are  configured and  the  thermoregulation requires  the  full  load start-up:  the  controller turns  the 
solenoid valve on, after 1 second the first motor part of the 1
st
 compressor (relay K1 of Fig. 2) and then the complete control with the 
contactor  K2.  Durning the  CO12  time  delay  the  step  valve  is  forced  on: minimum  power.  When  the  C012  is  expired if  the 
thermoregulation requires more power the valve will be switched off (maximum power). 
21 CAPACITY CONTROL 
Only the compressor 1 can be configured with 3 capacity step. 
CO06 capacity control operative mode. 
The relay configured as capacity control are managed by the thermoregulation as shown in the graph and into the tables here below. 
Par CO06 = 0 ON/OFF step 
0= Step control. Depending on the thermoregulation requests and the output polarity a power step can be enabled or disabled. The step 
is activated only after the previous is turned off. 
Eg: 1 capacity compressor with 3 partializations: 4 Power steps. 
Capacity  25%  50%  75%  100% 
Compr.  Compressor ON  Compressor ON  Compressor ON  Compressor ON 
Out relay  Step P 1 ON   Step P 1 OFF  Step P 1 OFF  Step  P 1 OFF 
Out relay  Step P 2 OFF  Step P 2 ON  Step P 2 OFF  Step P 2 OFF 
Out relay  Step P 3 OFF  Step P 3 OFF  Step P 3 ON  Step P 3 OFF 
Step control process  
Compressor  Part 1  Part 2  Part 3    Power involved 
          0 % 
          25 % 
          50 % 
          75 % 
          100 % 
Par CO06 = 1 direct action with sequential step 










