New Three-Phase Single Chip Energy Meter from Analog Devices

The ADE7752 simplifies three-phase meter design at a low cost

With 50 million meters already deployed using Analog Devices Energy ICs (ADE), Analog Devices extends its leadership by introducing the ADE7752 the highly anticipated three-phase electrical energy metering IC with watt-hour output.

The ADE7752 is the three-phase counterpart to the widely-used ADE7755 single-phase metering IC. Compatible with a wide range of three-phase grid configurations including direct connect and transformer operated, 3-wire and 4-wire distribution it can be used in three-phase commercial and industrial revenue meters or submeters, three-phase motors or generators, and industrial control and utility automation applications. Similar to other products in the ADE family, the ADE7752 achieves superior accuracy, with less than 0.1 percent linearity error over a dynamic range of 500 to 1, and operates with a single 5 V power supply. Accelerated life expectancy of 60 years and tight manufacturing qualifications ensure continuous performance of meters built with ADE ICs.

Single-chip, three-phase meter design is simplified with a built-in analog front end that is optimized for direct interface with a current transformer (CT). Furthermore, average real power in the form of two selectable frequency pulses can directly register energy consumption on a stepper motor counter display.

A negative power pin provides an alert if one or more of the three phases has negative active power flow. This indication is useful for detecting improper wiring during meter installation. The ADE7752’s active power accumulation is signed, but it can be set to accumulate based on the sum of the absolute value in each phase to ensure that energy is billed properly under mis-wiring or tampering conditions. Other features of the ADE7752 include no-load threshold and power supervisory functions. A low start-up current of 0.04 percent of basic current (I_b)ten times better than IEC standards eliminates any creep effect during a no-load condition, while power supervisory circuitry guarantees correct operation during power-up and power-down.

The Analog Devices website address is www.analog.com
[Reprinted with kind permission from Analog Devices]