Technische Alternative CAN-EZ3, Общая информация, Установка и подключение, Основные функции

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Heat meter
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Heat meter
Standard diagram
Function description
Calculation of thermal output and metering of thermal energy via the temperature differential
T.flow - T.return and the flow rate, and allowing for the antifreeze component in the heat transfer
medium.
Input variables
Enable General enabling of the function (digital value ON/OFF)
Flow temperature Analogue input signal for the flow temperature
Return temperature Analogue input signal for the return temperature
Flow rate Analogue input signal for the flow rate
Meter reset Digital pulse input signal, ON/OFF, to reset the meter
Specific heat capacity Optional : Analogue value specifying the heat capacity of the fluid in
the measured system
Price / unit A price per kWh for yield calculations
• The BFPT1000 5x60MM sensors fitted in the KH ball valve from Technische Alternative are
particularly suitable for temperature measurement. The sensors can be removed with little
effort for the calibration process.
• With a solar thermal system, the collector sensor can also be used as the flow sensor. For that
to be possible, it must be installed in a sensor well at the flow outlet of the collector header.
However, the captured amount of heat will then also include the losses in the solar flow line.
• Entering User as the source in the Flow rate input variable allows a fixed value to be entered as
the flow rate instead the flow rate captured by a flow sensor.
• The meter reset is carried out by a digital ON pulse or manually in the parameter menu. It will
delete all meter readings, in other words also those from previous periods. The meter will be
blocked as long as this input variable is set to ON. The meter reset also works when Enable =
Off.
• Specific heat capacity: This optional specification must be entered as a multiple of the unit
0.01 kJ/l*K as a dimensionless number. Example: Pure water has a heat capacity of 4.18 kJ/
l*K at 20 °C, so a dimensionless value of 418 must be entered for this heat capacity (at 20 °C).
N.B.: The heat capacity of fluids is temperature-dependent. The value entered should there -
fore be a variable value dependent on the temperature (e.g. from the Curve function).