Wonder why they chose to show cumulative time but not absolute? In other words, for instance, like with my fridge, which I am now checking the consumption of, when it is not running, the draw is 0.00 watts. Great. However, the accumulated time counter ONLY counts minutes while power is being drawn. So.... while it is great to know exactly how much time the fridge was on, this unit does not indicate the span of real time passing ... so I have to make sure to log precisely when I start a 24 hour test, and then when I stop it, and compute the usage myself. The official Kill a Watt meter is better at doing this for you.

Other than that, the unit is working fine, display is clear and legible, short extension cable is handy (could be longer!) and there's not much else to say. Very interesting to watch the variable draw of a computer's switching power supply depending on what you are doing.

The Poniie PN2000 is an easy to use and simple device after you read the instructions and various customer reviews in order to figure out the menu settings. The device is well made, the digital read out is easy to read, and it works just as described.

From the owners manual: The device can measure Watts (active power), Current (true RMS), Voltage (true RMS), Frequency, Cumulative Time (with hold over circuit memory), Electricity Consumption (with hold over circuit memory) and Power Factor (as Watts/Vrms*Arms).

The important numbers to figure power being used by an electrical device are the "cumulative time" and the "energy consumption".

You plug the meter in line with the device you want to monitor and then simply divide the cumulative time (this being the "stopwatch" time that the device is pulling power - if the electrical device is turned off for a while the timer does not keep adding minutes to the clock and picks up again when the device is turned back on, by the electrical consumption. The time is given in minutes so we find it easiest to figure out how many kilowatts were used by "the minute" and then multiply times 60 to get the power used in a kWh (kilowatt hour). For an item like a refrigerator that cycles on and off constantly you might want to leave the device connected for a lengthy period (perhaps 24 hours or longer) in order to get a more accurate power use profile as it cycles on, then off, then through a defrost cycle, and so on. Simple "on or off" devices might only need to be monitored for a half-hour or even less to find out the energy consumption.

Unfortunately, like many of Amazon's sellers these days, the Poniie PN2000 seller sends the buyer e-mail asking them to write a review of their product if they like using it. E-mail from sellers requesting the purchaser write a review is what has ruined Amazon's best feature, and those reviews are always suspicious as not only no. Too bad that the seller doesn't have enough faith in their product and has to prompt buyers to write a review.

To make it simple we divide the monthly electric bill total by the number of kilowatt hours used found on the monthly bill to get a per hour kW price, and then multiply that number times the kWh for the device we were monitoring (we're currently paying 0.12 cents per kWh).

Works easy with interesting functions - even to double check what my UPS gives in A/C voltage and line hertz. Backlight makes reading behind an appliance possible. Worth buying 3ft 14 or 12 AWG short extension cord for power measurements to bring meter out for easier reading. Accuracy is at least within 0.2 watts - likely better, but I lack a lab reference for finer power data. Poniie customer service is outstanding.

Love this tool. It's exactly what I needed to measure how much electricity my dehumidifier was using. I have the dehumidifier in my basement set to 55% humidity, and its draining into a sink. It auto shuts off when it reaches the desired humidity, so I know its not running 24/7, but there's no way to be sure for exactly how long it runs ever day and no way to estimate how much electricity it was costing me to run it. I bought this meter, plugged it in, and it gives me a cumulative reading for as long as I leave it plugged in. It gives me the cumulative kWh, as well as the cumulative minutes so I can just do the math and use my kWh cost to figure out how much the appliance is using. I'm going to use it on my window AC units next to get an idea. For the price, this tool is great to have. Love the backlight feature as well. The Poniie company seems to have excellent support too, as I've received several emails thanking me for my purchase and offering any help that I need using the product.

Only got it today, but appears to operate as advertised. Easy to use and multi-voltage. My only beef, is that the product has a label that says 110 volts input, but the manual and product page indicates multi-voltage. Normally, I would assume the product label was correct, and the manual was wrong, or was written to encompass multiple products with different specifications. Since the product page indicated multi-voltage, I rolled the dice and plugged it into my 220 volt outlet. It is definitely mutli-voltage. Works fine off of 220 volt input. You just need to change the default overload indication from 1800 to 3500 watts(220 volts X16 amps=3520 wats).

Also, under technical details(versus technical "specification") it also incorrectly indicates product as being for 115 volts. Even in the areas where it correctly identifies it as multi-voltage(110-240volts 50/60hz), it doesn't bother to list the maximum power if using 220 volts input versus 110 volts input. Power(wattage)=Voltage X Amperage. The power handling for 220 volts is double the power handling if using 110 volts. This could be confusing for those unlike me, who have been an electronic technician for 30+ years, and consider this basic knowledge.