ABB A43, Руководство пользователя

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Technical Description
2CMC48001M0201
57 A43/A44
Revision: C User Manual
Input coding, meters with 2 tariffs
The coding of the inputs is binary. The following table describes the default
cod-ing.
Input 3 Tariff
OFF = T1
ON = T2
5.5.2 Pulse Outputs
About pulse
outputs
Meters equipped with pulse outputs may have up to 4 outputs.
On the pulse outputs the meter sends out a specified number of pulses (pulse
frequency) per kWh (kvarh for reactive pulse outputs).
The pulse outputs are primary, which means that the pulses are sent out in propor-
tion to the true primary energy, taking current and voltage transformer ratios (CT
and VT ratio) programmed on the meter into account.
For direct connected meters no external transformers are used and the amount
of pulses sent out are in proportion to the energy flowed through the meter.
5.5.2.1 Pulse Frequency and Pulse length
General
Pulse frequency and pulse length can be set via the buttons on the meter or via
communication. If the meter have more than 1 pulse output, all outputs will have
the same pulse frequency and pulse length.
Pulse frequency
The pulse frequency is configurable and can be set to a value between 1-9999
impulses. The value must be an integer. The unit is selectable and may be set to
imp/kWh, imp/Wh or imp/MWh.
Pulse length
The pulse length can be set to a value between 10-990 ms.
Deciding pulse frequency/length
If the power is too high for a certain pulse length and pulse frequency, there is a
risk that the pulses may go into one another. If this happens the meter will emit
a new pulse (relay closed) before the previous one has terminated (relay open)
and the pulse will be missed. In worst case the relay may be closed at all times.
To avoid this problem a calculation should be made to work out the maximum
pulse frequency allowed at a particular site based upon an estimated maximum
power and the meter’s pulse output data.