Carrier ComfortLink 30HXA - Page 87

87
APPENDIX B (cont)
The following tables show the loading sequence for
30HX206 (57/43 split) and 30HX271 (67/33 split) chillers. All
compressors have two loaders and the chiller is configured for
staged circuit loading. Loaders A1 on compressors A1 and A2
are energized in parallel. The same is true for Loaders A2 on
both compressors A1 and A2. See Note 3.
LEGEND
NOTES:
1. Stage 3A is not used by the algorithm when increasing stages. Stage 3 is not used
by the algorithm when decreasing stages.
2. The % Total Capacities above are calculated based on compressor nominal tons.
For the case of the 57/43 split above, the 30HX uses compressors with flow rates
of 209, 123, and 250 cfm (from compressor model numbers 06N_209, 06N_123,
and 06N_250), which represent nominal tons of 66, 39, and 80 (respectively) at 60
Hz. A factor of 40% is used when no loaders are energized, and a factor of 70% is
used when Loader 1 is energized. The capacity shown for Stage 4 above is calcu-
lated as follows:
% Total Capacity=[(0.70 x 66 + 0.70 x 39 + 0.0 x 80)/(66 + 39 + 80)] x 100% =
39.7%
3. The loading sequence for 30GXN,R204-264 units is the same as those shown for
the 30HX206, 271 above.
STANDARD LOADING SEQUENCE (CIRCUIT A LEAD CIRCUIT, 3-COMPRESSOR UNIT)
STAGE
COMP
A1
LOADER
A1
LOADER
A2
COMP
A2
COMP
B1
LOADER
B1
LOADER
B2
% TOTAL
CAPACITY
(57/43 Split)
% TOTAL
CAPACITY
(67/33 Split)
0 00 0000 0 0.0 0.0
1 10 0000 0 14.3 13.3
2 11 0000 0 25.0 23.3
3 11 1000 0 35.7 33.3
4 11 0100 0 39.7 46.7
5 11 1100 0 56.8 66.7
6 11 1111 0 87.0 90.0
7 1 1 1 1 1 1 1 100.0 100.0
CLOSE CONTROL LOADING SEQUENCE (CIRCUIT A LEAD CIRCUIT, 3-COMPRESSOR UNIT)
STAGE
COMP
A1
LOADER
A1
LOADER
A2
COMP
A2
COMP
B1
LOADER
B1
LOADER
B2
% TOTAL
CAPACITY
(57/43 Split)
% TOTAL
CAPACITY
(67/33 Split)
0 00 0000 0 0.0 0.0
1 10 0000 0 14.3 13.3
2 11 0000 0 25.0 23.3
3 11 1000 0 35.7 33.3
3A 10 0100 0 22.7 26.7
4 11 0100 0 39.7 46.7
5 11 1100 0 56.8 66.7
6 11 1110 0 74.1 80.0
7 11 1111 0 87.0 90.0
8 1 1 1 1 1 1 1 100.0 100.0
0 — Off
1 —On