The Plugmeter board demonstrates a complete 15A, single-phase power meter for use with 110V/220V AC inputs, and includes a 2.4GHz RF module from Synapse Wireless which provides full mesh networking capabilities. OEMs can easily incorporate elements of the modular board in their product designs, giving end users the ability to track the electricity usage of products such as home appliances, plug strips, electric motors, servers and HVAC equipment.
At the heart of the Plugmeter is the MCF51EM256 from Freescale Semiconductor, a 32-bit microcontroller optimised for energy metering applications and including useful peripherals such as anti-tamper and calendar functions. It also includes an embedded 288-segment LCD controller, a 4 x 16-bit ADC, an independent real-time clock and up to 256kB of flash memory. A full suite of hardware and software development tools is provided with the Plugmeter, enabling the rapid development of energy-monitoring application code.
The MCF51EM256 is complemented by the SM700 2.4GHz RF module from Synapse running the SNAP wireless mesh networking software stack. (The 2.4GHz module can be replaced by an 868MHz RF module for operation in Europe.) SNAP supports the creation of self-forming, self-healing peer-to-peer networks, and thus enables the design of a network of Plugmeters controlled from a central point. The Plugmeter also offers a regulated power supply, an optically isolated USB port, 15A relay control for load management, and a Lumex LCD display.
The device provides ±1% accuracy and is suitable for consumer monitoring applications but is not intended to support utilities’ billing operations. The board consumes <1.3W from a mains input.
Colin Weaving, Technology Director of Future Electronics (EMEA), said: ‘With environmental awareness on the rise and energy bills soaring, there is now considerable consumer demand for individual appliances to show the user how much electricity they consume.
‘The Plugmeter reference board includes every function an appliance needs to show the user accurate power usage figures, but because it is designed in a modular way, OEMs can pick and choose which of these functions to implement.’
The Plugmeter is shipped with a complete design support package which includes a bill of materials, firmware, hardware design files and software to interface to a PC. It is available free to qualified customers.