Accuracy Of Energy Metering ICs Boosted

Two new metering devices have been developed that promise to monitor energy usage for utilities more accurately. Both ICs are based on a/d converter technology combined with a fixed-function DSP that focuses in on performing all energy measurement calculations and allowing use of a low-cost microprocessor for data management and supervisory functions. For mid-range, three-phase energy meters, the ADE7758 measures reactive, active and apparent energy, as well as RMS voltage and current, for each phase; power consumption is 70 mW. Measurements are accessed via a serial interface that also allows for automated digital calibration. Active energy measurements exhibit less than 0.1% gain error over a current dynamic range of 1,000:1. Designed for single-phase applications, the ADE7753 offers the same features as the ADE7758 while dissipating only 25 mW. ADE7753 and ADE7758 are available in 20-lead SSOP and 24-lead SOIC packages, respectively, priced at $2.52 and $6.88 each/1,000, respectively. ANALOG DEVICES INC., Wilmington, MA. (800) 262-5643.