Apator ELF User Manual

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characteristic points of the error curve of the flow transducer, followed by recording the value in the
electronic circuit memory module. This results in a smooth error chart over the entire flow range for
each transducer. The revolution value is not changed at actual flows which are above the maximum
value or below approx. one half of the minimum value; in this case calibration is inactive. The volume is
displayed as a value of seven digits with the accuracy of 1 dm
3
(litre). In order to perform quick metrolo-
gical tests, the heat meter can be switched to the test operating mode and enable the fast pulse output
according to the technical data table. An additional register of simulated volume is also enabled in the
test operating mode – see the test mode description.
5.1.3. Supply and return temperatures; differential temperature
The temperature values are determined by measuring the Pt500 sensor resistance. The RAM register
stores the supply and return temperature values of the medium with the calculated differential tempera-
ture value. Each temperature value is determined down to 0.001 °C, displayed with the accuracy of 0.01
°C and transmitted to remote reading devices with the accuracy of 0.1 °C of transmitted data.
If a failure or overflow of one of the temperature sensors occurs, the failure is signalled by issuing an
applicable error code and by displaying a flashing q symbol and the corresponding value in the given
temperature menu. If the sensor inputs are shorted or the temperature is below range, the value of
0.00 °C is displayed. If the circuit is broken or the temperature is above range, the value of 999.99 °C is
displayed. The same values are displayed for the temperature means determined during a temperature
measurement error. In both cases the displayed differential temperature is 999.99 °C, which is also
indicated with the flashing error symbol. The value transmitted to remote reading devices is labelled as
a value during error and it is displayed as 999.9 °C or 000.0 °C.
5.1.4. Power and flow
Instantaneous flow is determined by measuring the duration of one full revolution of the flow transdu-
cer rotor. The flow calculation accuracy error is below 4%. If as low as ¼ of revolution is not detected
in 8 seconds, the flow indication is reset to zero. In practical terms, it is a flow value which is appro-
ximately one half of the minimum flow value, yet it is higher than the starting threshold for the given
flow transducer type. Instantaneous power is determined as the product of instantaneous flow and
metrological test (see section 6.1.).
5.1.5. Pulse inputs
The heat meter can be connected to a maximum of four additional devices equipped with pulsers. The
user may configure the inputs as volumeters (water meters) or power meters. It is possible to deactiva-
te each input by setting the pulse constant to zero. If an input is deactivated, the meter status for that
input is omitted on the display and not transmitted in M-Bus frames. Only low frequency signals are
used; however, it is possible to order custom interfaces of any type which will convert the signals to
compatible pulses. Only the interfaces from Apator-Powogaz shall be used, since they ensure proper
interference protection of pulse inputs.
5.1.6. Error codes
This register is not displayed during correct operation (error code = 0); an error will be indicated by
the flashing symbol with the error code displayed in the basic data menu. The failure states of the
measurement system are indicated with the error codes meaning as follows:
• 1 – exceedance of minimum flow, error raised when average minute flow is other than zero and lower
than the minimum flow;
• 2 – no pulse from water metre and ∆T > 10°C in 24 hours (the user can modify both parameters: no
pulse period and temperature difference);
• 4 – return temperature sensor damaged or temperature outside of range;

Apator ELF Specifications

General

Brand	Apator
Model	ELF
Category	Measuring Instruments
Language	English