Posted to News on 24th Apr 2008, 10:47
Three-phase energy meter features detachable display
Carlo Gavazzi is launching a compact three-phase energy meter with a patented multi-application detachable display and dual-mounting technology. The new EM21-72D can be used either as a basic energy meter or multifunction meter and brings both simplicity and compactness to cost-allocation applications and building management systems.
The MID-compliant EM21 is said to be quick and easy to install and occupies just 72 x 72mm on panel doors or four-DIN units on the rail. The self-powered meter features Easyprog simplified programming and automatic adoption of the display to the selected application. Carlo Gavazzi's patented detachable display requires no batteries or electrical connections as it simply plugs into the base unit via one of the two possible slots. The LCD gives a visual warning if incorrect phase sequence is detected.
Seven sets of three variables can be selected for display, providing for active and reactive energy measurement or a complete set of 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).
As standard, an OPTOMOSFET pulse output provides fast and easy data transmission to PCs and PLCs for energy monitoring, while all electrical parameters of the installation can be sent via the optional RS-485 port for integration with a BMS (building management system) or 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 per cent RDG (V, A) and the meter is rated class B according to EN 50470-3 (class 1 of EN 62053-21), class 2 (kvarh) according to EN 62053-23. The meter is fully compliant with the Measuring Instruments Directive (MID) annexe MI-003.
The operating temperature range is -25 to +55degC and the front panel offers IP50 protection against dust and water ingress.
