Iskra MT 511 User Manual page 9

B
ASIC DESCRIPTION AND OPERATION
User's Manual
Description of the device
Measuring transducer is intended for measuring, analyzing and monitoring single-phase electrical
power network. It measures true RMS values by means of fast sampling of voltage and current signals,
which makes instrument suitable for acquisition of transient events. A built-in microcontroller calculates
measurements (voltage, current, frequency, energy, power, power factor, THD, phase angles, MD) from
the measured signals.
1.1.2 Appearance
Measuring transducer can differ from yours depending on the type and functionality.
1 – Communication ports and LED
indicators
2 – I/O modules
3 – Auxiliary supply
4 – Voltage inputs
5 – Current inputs
6 – USB-B type connector (option)
7 – RJ45 Ethernet connector (option)
Communication ports and LED indicators
Under the sliding, semitransparent cover are connectors for various communication types, which should
be chosen at placing the order. Serial communication can be connected through DB9 connector (RS232
or RS485) or screw-in connector (RS485 only). Ethernet communication can be connected through
standard RJ-45 type connector. USB can be connected through USB-B type connector. There is also
additional communication port (RS485), which is intended for Remote display connection (RJ-11 type
connector).
Two LED indicators are intended for POWER ON signaling (red LED) and COMMUNICATION IN PROGRESS
signaling (green LED blinking).
I/O modules
Two I/O module slots are intended for various I/O modules, which should be chosen at placing the order.
Digital inputs, analogue outputs, alarm / digital outputs and pulse outputs.
Auxiliary supply
Auxiliary supply is connected through three screw-in connectors. For safety purposes it is important that
all three wires (Line, Neutral and Earth) are firmly connected. Auxiliary supply can be either LOW (19
VDC – 70 VDC; 48 VAC – 77 VAC) or HIGH (70 VDC – 300 VDC; 80 VAC – 276 VAC), which should be
chosen at placing the order.
Voltage inputs
Each voltage input is connected to measuring circuit through input resistor chain (4.2 M per phase).
Maximum value of input voltage is 600 V
Current inputs
Each current input is connected to measuring circuit through current transformer (0.01  per phase).
Maximum allowed thermal value of input current is 15 A (cont.).
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