1592001431 XC650CX GB r3.5 21.07.2020 XC650CX 34/56
19. UNEVEN CAPACITY COMPRESSORS (CtyP = dPO)
With CtyP = dPO the regulation is performed for uneven capacity compressors
In this case the capacity supplied by the system is a combination of the capacity of different
compressors.
The capacity of each compressor ha sto be set in the parameters PC1…PC6.
The regulation algorithm supply a combination of the available capacities, starting from the
lower ones and increasing step by step according to the requests coming from the system.
With uneven capacity compressors, the algorithm doesn’t distribute the working time between
the various compressors to ensure even run times.
19.1.1 Regulation example
oA1 = CPr1, oA2 = CPr1, oA3 = CPr1, OA4 = CPr1, oA5 = nu, oA6 = nu.
CtyP = dPo
Pc1 = 10; Pc2 = 15 Pc3 = 30; Pc4 = 40
The transition between the various steps can be carried out only if the safety timers (onon, oFon, donF)
have been expired, otherwise the first available step is used.
20. SCREW COMPRESSORS (CtyP = Scr)
*******READ CAREFULLY BEFORE PROCEEDING*******
The controller doesn’t manage any time limitation on the activation of the 25% capacity
valve.
If the compressor is not design for a long activation of the 25% capacity valve, an external
device able to exclude this situation MUST be used. !!!!!
Dixell can’t be considered responsible for possible damages caused from this situation
The controller is able to manage only 1 screw compressor, operating on circuit 1.
Loads activation is managed by the neutral zone.
To set it:
CtyP = Scr: in this way the compressor is managed as screw compressor, and the relays set as
steps, will follow special activation rules, as explained in the following chapters.
The activation of the valve is designed according to the Bitzer, Hanbell compressors.
Set the relay oA1 = CPr1, it will manage the compressor.
Set the oA2, oA3 and oA4 as “StP”.