
Glossary
CI-3K50601 Project 2191 DMR2731 Rev.1 18-08-11
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8 Glossary
Active energy
Accumulated energy (Watt hours).
CT
Current Transformer. Transforms a (usually) high current to a value
that can be monitored by the meter.
Firmware
Software installed on a permanent medium.
Johnson Controls
(JC) N2
A master - slave serial communication protocol with fixed
communication parameters.
Modbus™
A proprietary communications protocol used for control and monitoring.
Reactive energy
The energy (VArh) in the reactive component of the supply. The
current and voltage in the reactive component are mutually 90
out of
phase - capacitive or inductive – resulting in a supply power factor of
zero.
RS485
A serial communication system linking multiple addressed terminals.
SCADA
Supervisory Control And Data Acquisition system.