Three-phase energy meter with detachable and reversible display
15 February 2013
Carlo Gavazzi has introduced a new version to its family of EM21 three-phase energy meters. The compact EM21-72V, designed specifically for retro-fit applications, measures current by means of an external split core current sensor, which when fitted limits the voltage to the meter to just 0.333V.
By using split core current sensor technology, no primary wiring modifications are needed in existing installations therefore there is no need to disconnect or modify the power cables during installation. The CTVs are available in five different ranges: 60A with 9.6mm hole diameter; 100A, hole diameter 15.5mm; 200A, hole diameter 15.5mm; 400A, hole diameter 20.5mm; and 800A, hole aperture 50x89mm.
As a result, the EM21-72V offers a simple to use metering solution for any retro-fit application which provides the opportunity to optimise and reduce any energy bills without modifying or disconnecting any wiring. Installation is faster and simpler, thanks to the meter’s self-power supply from the voltage reference inputs, automatic phase detection with wrong-phase-sequence warning and fast application-oriented programming procedure.
A selection of variables can be programmed providing for active and reactive energy measurement or a complete set from seven sets of 3-phase variables. Options include: system variables such as W, var, PF, Hz and phase-sequence; single-phase variables including A, VLL, VLN, PF; TRMS measurements of distorted sine waves; and energy measurements (total kWh and kvarh).
The EM21 family of meters feature a detachable display, which enables the meter to be mounted either on a front panel with just 72x72mm footprint, or on a DIN-rail in only four modules wide.
Available as either a Modbus and Pulse or Pulse only to provide fast and easy data transmission to PCs and PLCs for full load control, whilst all electrical parameters of the installation can sent via the optional RS-485 port for integration with BMS (Building Management Systems) and other standard acquisition-monitoring systems.
Instantaneous variables are displayed as 3 x 3 digits, with energy meter readings to 6+1 digit resolution. Accuracy is ±0.5% RDG (V, A), and the meter is rated Class B (kWh) according to EN50470-3 (class 1 of EN62053-21), Class 2 (kVarh) according to EN62053-23.
Operating temperature range is from -25°C to +55°C and the front panel offers IP50 protection against dust and water ingress.
Contact Details and Archive...