with Three-Digit Display AC Current, Voltage, Frequency Indicator, 22mm Square Head LED Multi-Function Measuring Instrument Monitor (Green)

I installed it on a little generator and it display accurate. However when it was operating at 60hz the display vibrated so violently within its housing that it was a blur. The clear lens can be pried off by gently inserting the tip of a utility knife to free the tangs at the top and bottom of the lens from the grey housing. Now you can put down a bead of ShoeGoop or electronics grade silicone (all other silicones damaged circuitry) between the display block and housing. Replace lens before it cures. This will prevent the circuit from vibrating apart.

Great way to tell how much your loading up your generator.

This compact triple meter is perfect for non critical measurements. The voltage and frequency values are spot on, current readings below 4 amps are hit or miss. As mentioned in other reviews, if you double up the loop running through the CT, you can get decent lower current readings. I purchased 4 of these meters, 3 for my generator monitoring panel and 1 for my bench top power supply. In both cases the voltage and hertz values are dead on. The current, while a nice touch, is not a big deal.Good value, hopefully they will last.

Ham radio power supply projects. good product, easy to include in a project and cheap too

Installed this unit in conjunction with a load transfer switch. Seems very accurate including the amps measurement. I did double the load wire through the sensor ring as was suggested by others.

Garbage

I am using this meter on a generator that didn’t have a frequency meter, but does have an electronic engine speed governor. I am able to adjust the engine speed at no load and, with a frequency meter, able to see the droop at full load. This meter read 63 hz so I adjusted the Genset down gradually. The meter went from 63 to 60, but never registered 61 or 62.In disbelief, I increased the speed slightly to find 61 hz. Never happened. I put my Fluke meter on the same input lines as the meter and read 61.5 hz.I am not able to get any readings from this meter between 60 and 63 hz. That being said, the ammeter and voltage readings were valid.It would have been appreciated if the seller had stated this in their listing.

I used two of these on my Harbor Freight Predator 4000 generator to view the balance of load across the two hot lines. You need to power the device itself from the circuit being tested and of course run the lead being measured through the coil. Minor issue that display is hard to read in sunlight, so you'll need to shield display while reading. Nice to have voltage, current and freq because it confirms that the power quality is pretty good (held 60 hz through the entire load).