Ultraflux UF 801-P, Руководство пользователя

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18.1 Introduction
This function involves optional acquisition modules and function.
When equipped, the UF 801-P can measure the heat flow rate (K Watt) and the
heat quantity (K Watt-h). Such a calculation that can be done manually later from
records of actual flow and temperatures is here automatically done in the unit.
The applications allow for the performance testing such as heat exchangers,
boilers, the power and energy sent to a building for central heating …and is
applicable to cold exchangers as well
To keep the flexibility of a non-invasive measurement, as it is with ultrasonic
clamp-on probes, we propose to install clamp-on thermal sensors, as PT100 /
PT1000/Din quality. Insure the best coupling to the pipe with a heat conductive
paste. If invasive probes exist, they should offer a better accuracy, thus we
recommend using them.
We recommend our new modules for PT 100/PT1000, with possibility of 2, 3 or 4
wires connection to optimize cable length compensation. They offer a typical
accuracy of +/- 0.1°C.
The temperatures can also be acquired through analogue input modules.
Comment on heat flow accuracy: Supposing a delta T°C of 20 °C between the inlet
and outlet of the circuit, an error of +/- 0.5 °C on each T acquisition can make 5
% error on the heat flow energy. Thus, it can be important to do better.
18.2 Typical installation on a heater
Equipped with this function and two T probes, the UF 801-P measures and
displays the two temperatures (inlet and outlet), their difference and compute
the energy flow from the raw flow rate and the characteristics of the fluid.
Actual Energy flow (delivered or exchanged) is displayed in kW and Energy is
totalised in kWh.
So, it is easy to control the efficiency of an heater or an heat pump, or a thermal
exchanger by comparing results to energy consumption.
Cold water inlet
Hot water outlet
Heater
Mesure Q
T°1 meas
t
T°2 meas
t
Flow probe