Kamstrup 162M, Техническое описание

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TECHNICAL DESCRIPTION Kamstrup 162M/382M
5512-1040 GB/05.2012/Rev. C1
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2.2 Construction
The meter is designed as a three-piece plastic construction, consisting of housing, verification and meter covers,
all parts made of fire resistant plastic. The verification cover protects the metrological functions. It is not possible
to open the verification cover without breaking the metrological seal.
The meter cover covers the module area. Various communication modules, input/output and control modules can
be connected without reverification. Furthermore, the meter cover can be ordered with different lenghts. A short
version allows premounted terminal-pins or wires to be mounted, while longer version covers the terminal in- and
outputs
2.2.1 Terminals
The current terminal is a combined terminal and shunt. The terminal is the elevating type with one screw per
terminal, which secures quick and simple mounting. The construction and design of the terminal protect the
connected cable from being damaged during tightening. Furthermore, a good contact area is provided, which
minimises the contact resistance and thereby heating at heavy currents.
2.2.2 Measurement Construction
The meter is provided with 1 shunt per system for current mesurement, and it measures the voltage through a
voltage divider. A switch mode supply feeds measuring circuits and main processor with voltage. Furthermore, the
switch mode supply in combination with varistors and power resistors functions as an excellent transcient
protection.
The use of shunt and switch mode supply also makes sure that the meter is immune to magnetic influence.
Magnetic influence will be detected by the integral sensors and be registered in the meter’s event logger.
Using shunt as measuring principle for the current measurement where a resistance stable metal provokes a
given drop of voltage at a given current, makes the energy measurement secure and reliable. Another important
advantage of the measuring principle shunt is a linear change of the voltage drop, which is an expression of the
current consumption.
The meters are constructed with independent and galvanically separated measuring systems (the number of
measuring systems depends on the meter type). This ensures a correct measurement irrespective of how many
and which measurement systems are used.
The meter’s main processor with corresponding data logger has its own supply, which means that data is well
secured against transients.
Like voltage drop, energy consumption is calculated as an expression of the current compared to the phase
voltage and time. The energy registration per measuring system is communicated to the meter’s legal processor
via the meter’s internal bus system. After correction, the energies are summed in the main energy register.
Measured and calculated data is safely stored in the memory (EEPROM) and can be read out either via the module
area’s unique interface, or through the optical interface by means of an optical head.