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Parameters of the
PWM pump (installer)
NqmodNenn
Parameters of the
PWM pump
NqmodMin
NqmodMinBw
Parameters for
temperatures
TkSnorm
TiAussenNorm
dTkTrNenn
dTkTrMax
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HVAC Products
Mandatory settings! Parameterization to be made by the installer.
Speed at the design point of the heating plant. This value must be set at the time the
plant is hydraulically balanced.
It corresponds to the speed of the circulating pump at the design point for reaching the
nominal volumetric flow.
This parameter corresponds to the analog speed selector of the circulating pump, so to
say.
For the control, setting of the «NqmodNenn» speed corresponds to the volumetric flow
of 100 % (= nominal flow at the design point).
The settings for the reduced volumetric flow («NqmodMin» and «NqmodMinBw») refer
to this 100 % value.
Settings to be made if required.
Minimum speed of the PWM pump in heating operation that may be used so that a
sufficient supply of heat to the rooms is still ensured.
The adjusted percentage value is converted to a minimum characteristic depending on
the selected speed characteristic or the «NqmodNenn» speed.
This means that if «NqmodNenn» is changed, «NqmodMin» will automatically produce
another minimum speed for heating operation.
Minimum speed of the PWM pump in the case of stratification torage tank applications.
This pump speed is used when the stratification storage tank is fully charged.
The adjusted percentage value is converted to a minimum characteristic depending on
the selected speed characteristic or the «NqmodNenn» speed.
This means that if «NqmodNenn» is changed, «NqmodMinBw» will automatically
produce another minimum speed for DHW heating.
Mandatory settings! Parameterization to be made by the installer.
Maximum boiler temperature setpoint for the heating circuit. The maximum boiler
temperature setpoint or the nominal design temperature of the radiator heating system
refers to the design point at the design outside temperature «TiAussenNorm».
At the design outside temperature (lowest outside temperature), a 70 / 50 system is
designed based on a maximum boiler temperature of 70 °C.
This means that the «TkSnorm» setting to be made for a 70 / 50 system is 70.
Design outside temperature at the design point of a heating plant.
The design outside temperature (lowest outside temperature) for the respective
geographical region can be obtained from appropriate tables (e.g. VDI-Wärmeatlas, DIN
standard).
The maximum boiler temperature setpoint «TkSnorm» will then be set according to the
design outside temperature.
Mandatory setting!
Design differential (= temperature differential between flow and return) at the design
point at the design outside temperature. In the case of a 70 / 50 system, the setting to
be made is thus 20.
Setting to be made if required.
Maximum differential or ∆T between flow and return that shall be maintained by the ∆T
supervision.
Basic Documentation LMU54... / LMU64...
3 Functions
CC1P7494en
07.11.2002
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