1592001850 XC660D GB r3.4 04.09.2017.docx XC660D
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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
STEP
Pc1 = 10;
Pc2 = 15
Pc3 = 30;
Pc4 = 40
SYSTEM
CAPACITY
1
ON
-
-
-
10
2
-
ON
-
-
15
3
ON
ON
-
-
25
4
-
-
ON
-
30
5
-
-
-
ON
40
6
-
ON
ON
-
45
7
ON
-
-
ON
50
8
-
ON
-
ON
55
9
ON
ON
-
ON
65
10
-
-
ON
ON
70
11
ON
-
ON
ON
80
12
-
ON
ON
ON
85
13
ON
ON
ON
ON
95
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*******
T
he 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.
Summary of Contents for XC660D
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