Mitsubishi Electric CRHV-P600YA-HPB Service Handbook page 99

[ VII Control ]
Control at Initial Start-up
-8- Peak-demand control
General idea about demand control in the system with a combination of a heat pump and a combustion-type hot water boiler.
→During peak-demand hours, the operation of the air conditioning units is given higher priority than that of the heat pump units.
1.Individual system
The peak-demand control function is a function that restricts the maximum capacity of the units. The maximum operation
capacities of the units are restricted to specific levels relative to the maximum capacity of the units (= the compressors are
operating at the maximum rotation speed (100 Hz on the unit described in this manual)) being set as 100%.
80%
Preset value
2.Peak-demand control in a multiple system
The peak-demand control function is a function that restricts the maximum capacity of the units. The maximum operation
capacities of the units are restricted to specific levels relative to the maximum capacity of all units (= the compressors are
operating at the maximum rotation speed (100 Hz on the unit described in this manual)) being set as 100%.
Standard operation
The units are designed to operate in the patterns as shown below to optimize operation efficiency.
a. Maximum capacity setting (D%) ≥ 70% → All units will be operated at D Hz.
% %
400 <100 >
%
320
%
<80 >
Preset value
Entire system
b. Maximum capacity setting D% < 70% → The number of units "N" and the capacity at which the units operate "α" will be
1 ) D × M = 70% × (N-1) + α × 1 (40 % ≤ α < 70 % )
(N-1) units will be operated at 70 Hz, and one unit will be operated at α Hz.
%
400 <100%>
200%
<50%>
Preset value
Entire system
2 ) D × M = α× N 70% ≤ α, The α value will be set to a value as close to 70 Hz as possible.
N units will be operated at α Hz.
%
400 <100%>
200%
<50%>
Preset value
Re-distribution of capacity Re-distribution of capacity Re-distribution of capacity
%
400 <100%>
240%
<60%>
Preset value
Nomenclature
Maximum capacity setting:
D %
The capacity of the system when all units are operated at 100 Hz will be set as 100%.
M Total number of units
N No. of units in operation (calculated value)
α % ( α Hz) Operating capacity (calculated value)
HWE1312A
100%
The compressor will operate at the maximum rotation speed of 80 Hz.
(100Hz)
Distribution of capacity
No. 1 unit No. 2 unit No. 3 unit
determined so that either the condition (1) or (2) below is met.
70% 70% 60 %
No. 1 unit No. 2 unit No. 3 unit
No. 1 unit No. 2 unit No. 3 unit
70% 70% 70 %
Re-distribution
of capacity
80% 80% 80 %
- 92 -
The maximum capacity of each unit is set as 100%.
(The figures in the angle brackets indicate the total
capacity in the entire system.)
100%
80%
No. 4 unit
0 %
No. 4 unit
No. 4 unit
α :30% < 40 %
0%
note. During the heating season, the unit will
not be operated at 100 Hz to save
energy consumption in the first place,
so the unit's performance may not be
affected even if the maximum capacity
setting is changed.
GB