MULTICAL® 302
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Kamstrup A/S · Technical Description · 5512-1334_F1_GB_12.2016
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General description
MULTICAL
302 is a static heat meter, cooling meter or combined heat/cooling meter based on the ultrasonic
principle. The meter is intended for energy measurement in almost all types of thermal installations where water is
used as the energy-conveying medium.
According to EN 1434 MULTICAL
302 can be designated a "hybrid instrument", also called a compact meter. During
production and initial verification in our factory the meter is treated as three separate units or ”sub-assemblies” (flow
sensor, calculator and temperature sensor pair) but after delivery the units must not be separated unless by an
accredited laboratory.
If flow sensor, calculator or sensor pair have been separated and the seals broken, the meter is no longer valid for
billing purposes. Furthermore, the factory guarantee no longer applies.
MULTICAL
302 employs ultrasonic measuring technique, ASIC and microprocessor technology. A single board
construction comprises all calculating and flow measuring circuits, which provides a compact and rational design and,
in addition, exceptionally high measuring accuracy and reliability is obtained.
Volume is measured using bidirectional ultrasonic technique based on the transit time method, proven a long-term
stable and accurate measuring principle. Two ultrasonic transducers are used to send sound signals with as well as
against the flow. The ultrasonic signal travelling with the flow reaches the opposite transducer first. The time difference
between the two signals can be converted into flow velocity and thereby also volume.
The temperature sensor type is Pt500 according to DS/EN 60751. Accurately matched Pt500 sensors measure the
temperatures in inlet and outlet pipes. MULTICAL
302 is supplied with a ø5.2 mm Pt500 sensor pair. One temperature
sensor is mounted in the flow sensor from the factory and the other sensor is typically mounted as short direct sensor
in e.g. a ball valve.
The accumulated heat energy and/or cooling energy can be displayed in kWh, MWh or GJ, all in the form of seven
significant digits and measuring unit. The display has been specially designed to obtain long lifetime and sharp
contrast in a wide temperature range.
Other reading options are: accumulated water consumption, operating hour counter, current temperature
measurements, current flow and power readings. Furthermore, MULTICAL
302 can display loggings, target day data,
error hour counter, max. flow, max. power, information code and current date/time.
MULTICAL
302 is powered by an internal A-cell lithium battery with 6-8 years' lifetime or by two A-cells with 12-16
years' lifetime.
MULTICAL
302 is available with communication for either wired M-Bus and/or Wireless M-Bus.
In designing MULTICAL
®
302 great importance has been attached to user comfort and compact external
measurements, which makes it suitable for a wide range of applications.
This technical description has been written with a view to enabling operations managers, meter installers, consulting
engineers and distributors to utilize all functions comprised in MULTICAL
®
302. Furthermore, the description is
targeted at laboratories performing tests and verification.