Demand Control Overview - Mitsubishi Electric PUHY-M200YNW-A1 Service Handbook

[2-5 Demand Control Overview ]

2-5

Demand Control Overview

(1) General outline of control
Demand control is performed by using the external signal input to the 1-2 and 1-3 pins of CN3D on the outdoor units (OC).
Between 2 and 4 steps of demand control is possible by setting DIP SW6-8 on the outdoor units (OC).
No Demand control switch
(a) 2 steps(0-100%)
(b) 4 steps(0-50-75-100%)
*1. Available demand functions
(E)M200-(E)M500YNW models (single-outdoor-unit system): 2 and 4 steps shown in the rows (a) and (b) in the table above
only.
*2. External signal is input to CN3D on the outdoor unit.
*3. If wrong sequence of steps are taken, the units may go into the Thermo-OFF (compressor stop) mode.
Ex) When switching from 100% to 50%
(Incorrect) 100% to 0% to 50% : The units may go into the Thermo-OFF mode.
(Correct) 100% to 75% to 50%
*4. The percentage of the demand listed in the table above is an approximate value based on the compressor volume and
does not necessarily correspond with the actual capacity.
*5. Notes on using demand control in combination with the low-noise mode
To enable the low-noise mode, it is necessary to short-circuit 1-2 pin of CN3D on the outdoor unit whose SW6-8 is set to
OFF.
When SW6-8 is set to ON on the outdoor units, the following operations cannot be performed.
Performing 4-step demand in combination with the low-noise operation in a single-outdoor-unit system.
(2) Contact input and control content
1) SW6-8: OFF (Compressor ON/OFF, Low-noise mode)
CN3D 1-3P
Open
Close
CN3D 1-2P
Open
Close
*1. When SW6-8 on the outdoor unit in one refrigerant circuit system is set to ON , this function cannot be used.
2) When SW6-8 on one outdoor unit in one refrigerant circuit system is set to ON (4 levels of on-DEMAND)
CN3D 1-3P
Open
Short-circuit
*3. Input the order to CN3D on the outdoor unit whose SW6-8 is set to ON.
Note the following steps to be taken when using the STEP DEMAND
(Example) When switching from 100% to 50%
If the step listed as the wrong example above is taken, thermo may go off.
The percentage of the demand listed in the table above is an approximate value based on the
compressor volume and does not necessarily correspond with the capacity.
When this function is enabled, the night mode cannot be enabled.
BS_02_E
DipSW6-8
*1
Compressor ON/OFF
Compressor ON
Compressor OFF
Low-noise mode
OFF
ON
Open
100% (No DEMAND)
0% (Compressor OFF)
(Wrong)
Demand control
steps
(Correct)
Input to CN3D *2
OC
OFF OC
ON OC
CN3D 1-2P
Short-circuit
75%
50%
100% 0% 50%
100% 75% 50%
(*3)
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