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6 Instrument Description
6.1 Introduction
X3M is a microprocessor based energy analyzer with high flexibility and accuracy.
The patented digital measuring system guarantees high performance with age and thermal stability. This is
achieved through sophisticated strategies of automatic offset compensation - used throughout the
measurement chain – and through a Phase Locked Loop (PLL) sampling probe.
The real time sampling of the three phases voltage and current, makes it suitable to supervise the voltage
and quick current variations quality.
It can verify when a maximum or minimum threshold is exceeded in every single voltage/current cycle
The automatic rescaling feature on current inputs allows a wide measuring range - from
20mA
to
6A
in
direct connection.
All “true-RMS” measures are obtained with continuous sampling of the voltage and current waveforms: this
guarantees maximum precision even when rapidly changing loads are present (e.g. electric welding
machines).
X3M can be programmed to analyze three phase networks, both on three and four wires with low or high
voltage with 1, 2 or 3 CTs in addition to single phase measurements. The option of setting any required
conversion factor on the voltage and current inputs makes X3M suitable for use in both high and low
voltage networks.
It can measure the energy and the Maximum Demand on the 4 quadrants (active, reactive and apparent)
divided according to the Tariff time bands with internal calendar. The instrument can handle 2 different
calendars, one of which operates while the other can be automatically activated at a programmed date and
time.
It contains a 2MByte flash disk memory where data are stored according to record files according to
ModBus standard and can be read and written using the ModBus functions: “write general file” and “read
general file”.
The time is kept by a compensated, stabilized quartz clock and can be extracted in most required formats.
By programming the time zone, the changes from standard to daylight saving time are automatically
handled in any country. The clock has a backup battery, with a 15 year lifetime, and can be set either
using the modbus protocol or the keyboard.
The instrument firmware is kept in flash memory and can be updated through a serial port, using the same
communication protocol. The upgrade uses special security provisions to ensure continued operations
even in presence of communication failures.
All input, output, and power supply ports are electrically separated for maximum safety and noise reduction
under any operating conditions.
The in-house testing and calibration process is completely automated: a conformity certificate and
calibration report are supplied with each unit.
The custom designed LCD display has three 3 ½ digit lines and a 7 digit line and an extended symbol and
character set, allowing the simultaneous display of 4 measurements. Three 11-segment bar graphs give
immediate feedback on the overall measuring process.
The wide keyboard, with its 9 silicon rubber coated keys, clearly marked with function, allows a simple and
intuitive use of the instrument.
X3M is completely programmable, from either the keyboard or a PC remote connection (only for models
with communication port). It is therefore the ideal solution for all the power measurement and management
needs in the industrial environment.
The instrument is equipped with two optically insulated transistor driven outputs with capacity load of 27
Vdc 27 mA according to 43864 Din standard.
They can be used either as pulse output or as alarm and are fully programmable by the user on different
parameters and with different pulse frequency and duration.
The factory setting is with one output is proportional to the active energy, while the other to the reactive
energy and an output frequency of 1000 pulses per kWh (or kvarh) and 50 ms pulse time.
The pulses number is referred to the instrument end of range without the CT and VT scale factors.
