Digital Power Meters

Digital Power Meter The Brand Electronics line of Digital Power Meters make it simple to determine how much energy an appliance or light is consuming.  As the diagram below shows, plug the Meter into the wall outlet and then plug the appliance into the meter.  The meter then shows you how much power the appliance is currently consuming and how much total energy the appliance has consumed since the meter was last reset.  Other useful readouts are available, depending on model number (more info below).  

Check out our special section devoted to energy-saving refrigerator replacements.  The Brand Power Meter is an excellent tool for predicting savings:  Click Here for Refrigerator Replacement Page.

Power Meter Plug-in Diagram

AwardRead the outstanding review that the Digital Power Meter received from the Home Power magazine!    PDF Icon Home Power Review Article (46 KB)

Key Uses

  • Find the Large Electricity Users in a Home.  Did you know that a water bed can cost $15 per month to heat?  A portable HEPA air cleaner can also use a similar amount.  The monitor on your computer probably uses twice as much power as the system unit (my monitor uses 90 Watts while the main system unit only uses 45 Watts).   The Digital Power Meter makes it easy to measure the energy use of these appliances and measure the savings from efficiency measures that you may apply to the appliance.
  • Measure Intermittent Loads.  Appliances such as refrigerators, air conditioners, electric heaters, and computer printers cycle on and off periodically or vary their power draw.  Measuring the power at one point in time will not give an accurate picture of the monthly energy use of the appliance.  Because the Digital Power meter is an accumulating meter, it can accurately predict the consumption of these intermittent appliances.  Just leave the power meter connected to the appliance for a representative time period, and the meter will show the total energy consumed, including low and high use periods.
  • Do Time-of-Use Energy Studies.  With the new 21-1850CI datalogging model, you can record up to 8,121 average power readings at intervals as short as 1 minute or as long as 2 hours.  After downloading this data to a PC (running Windows 95/98) via a serial port, you will know the exact time pattern of power consumption for the appliance.  The meter is very useful for demand-side utility studies.  The internal datalogger is battery-backed, so data integrity is not affected by power outages.
  • Help Diagnose Equipment Problems.  For example, your computer won't turn on.  The Digital Power meter can tell you whether the power supply is working and how much power it is drawing.  This could save valuable diagnosis time.


  • Measures the Real Power Consumed by an Appliance.  A common misconception is that power is the product of voltage and current and can be determined by a standard multimeter.  This is only true in a few special cases, such as incandescent light bulbs and appliances where all the power consumed is due to electric heating elements.  For most AC appliances, the current waveform is out of phase with the voltage or the waveform is distorted.  Measuring the real power consumption, which is what the utility company measures and charges for, requires a sophisticated device such as the Digital Power Meter.
  • Measures Voltage and Current 4,000 times per second for Accurate Power Measurement.  By performing so many measurements in a second, the Digital Power Meter can accurately measure power from unconventional power sources such as battery-powered inverters or generators with non-standard frequency.  Also, appliances that draw complex current waveforms, such as most electronic devices, are accurately measured with the Digital Power Meter.
  • All Models Provide 4 Important Displays:

Diplay Mode 1   This display shows how much power (145 Watts) the appliance is currently consuming and how much energy (83 kilowatt-hours) the appliance has consumed since the meter was last reset.

Diplay Mode 2   This display shows how many hours have elapsed (32.1 hours) since the meter was last reset.

Diplay Mode 3   This display shows the cost of the of the energy consumed by the appliance ($22.10) since the meter was last reset..  It also shows the electric rate (10 cents/kWh) that is used in the cost calculation.  This rate can be changed by the user through use of the front panel buttons.

Diplay Mode 4   This display estimates how much the appliance will cost to operate for one month ($12.46).   It uses the electric rate and the total energy consumed since the meter was last reset to estimate the value.

The 20-1850 and 21-1850CI models also include displays that show Amps, Volts, Power Factor, VARS, Volt-Amps, and Peak Watts.  The 21-1850CI model includes the datalogging feature described above.

A dual-range option, 185 Watt / 1850 Watt range, is available for all power meters.  This option allows you to accurately measure and display power in 0.1 Watt increments up to 185 Watts.  The normal 1850 Watt range displays readings in 1 Watt increments.

The 4-1850 WX model has the same general specifications as the 4-1850 with an added peak wattage measurement feature, useful for determining if a refrigerator has gone through a defrost cycle during the monitoring period.  Click here for more info. 


Description Part Code Price
Model 4-1850:  Basic model that measures appliances up to 1850 Watts.  Includes the 4 main displays shown above. BE-4-1850 $ 149
Model 4-1850 WX: 4-1850 Digital Power Meter designed for Weatherization Audits, including a special peak power measurement for monitoring refrigerators. BE-4-1850 WX $167
Model 4-1850 DR:  4-1850 Power Meter with Dual-Range 185/1850 Watt option for reading power in 0.1 Watt increments up to 185 Watts. BE-4-1850 DR $ 169
Model 20-1850:  Adds Amps, Volts, Power Factor, VARS, Volt-Amps, and Peak Watts readouts to the capabilities of the 4-1850. BE-20-1850 $ 249
Model 20-1850 DR:  20-1850 Power Meter with Dual-Range 185/1850 Watt option for reading power in 0.1 Watt increments up to 185 Watts. BE-20-1850 DR $ 269
Model 21-1850CI:  Same advanced features as the 20-1850, but adds the capability to log average power readings to memory inside the meter.  Then, download the readings to a PC for analysis.  8121 Samples, stored at user-selectable 1 minute to 2 hour intervals.  Requires PC with Win 95/98 (not compatible with NT) and one serial port. BE-21-1850CI $ 349

See the Specifications and Features table for more information on the different models.

Digital Power Meters carry a 14-day, money-back guarantee.  If you are not satisfied with the product for any reason, simply return the product within 14 days after you receive it, and we will refund the purchase price.

Go to our Orders Page to find out how to order a Digital Power Meter.

Brand Electronics Digital Power Meters carry a 6 month warranty.  Power meters are warranted to be free of defects in craftsmanship and materials for that period.   Defective units will be repaired or replaced by Brand Electronics during that period.  Repairs outside of that period are charged at a flat $40 rate by Brand Electronics.