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Building Technologies
Modular Heating Controller RMH760B
CE1P3133en
HVAC Products
10 DHW heating
05.02.2007
31
33
S
85
A
B
A
The boiler pump is located at A and
required
as a system pump for DHW heating.
Input: System pump required = Yes
B
The boiler pump is located at B and is
not
required for DHW heating.
Input: System pump required = No
10.11.6 Consumer control
Any DHW plant type can be equipped with consumer control.
This function offers the choice of combining high storage tank setpoints with a reduced
risk of scalding by using lower consumer setpoints, for example. This can help to make
optimum use of a given storage tank volume.
In that case, consideration must be given to the fact that higher water temperatures
lead to the formation of more scale in the plant.
31
33
S
86
CiPu
Consumer control always consists of mixing valve and consumer flow temperature
sensor.
The circulating pump is an optional plant component, but recommended.
When there is no flow of water, the mixing valve can fully open, which can lead to high
outlet temperatures once the flow starts again.
Consumer control is to be activated via “Extra configuration”:
… > DHW… > Inputs > Flow sensor consumers
Assign terminal
… > DHW… > Outputs > Consumer mixing valve 3-pos
Assign terminal
… > DHW… > Outputs > Consumer mixing valve mod
Assign terminal
To be able to match the control parameters to the type of plant (actuator and controlled
system), the parameters of the PID controller can be set. They apply to both 3-position
and DC 0…10 V actuators.
Main menu > Commissioning > Settings > …
or
Main menu > Settings > DHW > Controller consumers
Operating line
Range
Factory setting
Actuator run time
1…600 s
35 s
P-band Xp
1…100 K
50 K
Integral action time Tn
0…600 s
60 s
Derivative action time Tv
0…30 s
0 s
The operating mode is only dependent on the time switch of the circulating pump,
whereby operating mode “Normal“ applies during “On”, and operating mode “Reduced“
during “Off”.
The operating mode of consumer control indicates the setpoint at which the consumer
temperature is maintained.
Example
Extra configuration
Settings
Operating mode