CrocSee AC 80-260V 100A CRS-022B LCD Display Digital Current Voltage Power Energy Frequency Power Factor Multimeter Ammeter Voltmeter with 100A Split Core Current Transformer

This is an excellent product that I continue to be very happy with. I wanted to mention a few things that might be useful to potential buyers.1. Expanding on the instructions of how to reset the total energy to zeroThe instructions say to hold the button down for 5 seconds until the energy value flashes and then release the button and tap it once again. That's the correct procedure, but what might be confusing is that there's an intermediate event that's not mentioned.When you press and hold the button, after 3 seconds the main display disappears and the words SET CLr appear. Since the energy numbers didn't start blinking but instead the screen with the energy numbers just disappeared from view you might be tempted to release the button. But don't do that! Instead keep holding the button for another couple of seconds and the main screen will reappear with the energy numbers flashing. ONLY THEN can you release the button and tap it once more to zero the energy value.2. Understanding the precision of the energy numbersNote: In what follows I'm using the term "precision" to indicate the precision of what can be displayed, not reproducibility of repeated measurements.Because the energy display has only one fixed position for the decimal point - to the right of the leftmost digit - there are some limitations on the precision that can be displayed in different energy ranges, particularly above 10 kWh. I've attached some photos to illustrate this.The device has an energy resolution of 1 watt-hour (Wh). It won't display, for example, 0.5 Wh. A photo shows a display of 002 Wh.Many people will want to look at energy use above 100 Wh, and at that point the device begins displaying three significant digits. A photo shows a display of 132 Wh and another at 896 Wh. The measurement uncertainty in this range is 1 Wh. For example in the 132-Wh photo we know the energy is at least 132 Wh but less than 133 Wh. At 100 Wh this would represent a 1% uncertainty and it would be a 0.1% uncertainty at 999 Wh, just before the display mode changes.Above 999 Wh the decimal point appears and the display units change to kilowatt-hours (kWh). There are still three significant digits because the energy is displayed with two decimal places. Photos show 1.23 and 9.52 kWh. Just as in the previous display mode, the uncertainty beyond the last digit represents 1% at 1.00 kWh and 0.1% at 9.99 kWh.But at 10 kWh the fixed-position decimal point comes into play and things change. Because there is no position for a decimal point between the second and third digits the display can't show 10.0 but instead has to show 010, which is shown in a photo. This means that we know the energy is at least 10 kWh and less than 11 kWh. This 1 kWh uncertainty represents 10% at 10 kWh - far higher than the precision associated with measurements up to now. Obviously this 1 kWh uncertainty will become less important at higher energy ranges, representing 1% at 100 kWh and 0.1% at 999 kWh, the maximum energy that can be displayed. But it may be to much for some users wanting precise energy measurements closer to 10 kWh.To summarize, in the energy range from 100 watt-hours to 10 kilowatt-hours the device can display energy with a precision no worse than 1% and as good as 0.1%, which may be perfectly adequate for most users. Users who want to make careful measurements in the 10-30-kWh range - which may include PHEV owners and those partially recharging EV's - need to be sure that they understand what the display is capable of in this range.3. Exceptional customer-service experienceI bought two of these units in April, 2022. After making the measurements I needed I put them aside. In January 2025 I need to make some further measurements but had problems reliably resetting the energy to zero (which later turned out to be my own misunderstanding. See item 1.) I contacted CrocSee's customer service, hoping that they could tell me what I was doing wrong. Instead they offered to replace the units even though they had been out of their one-year warranty for almost two years! I very much appreciated this exceptional customer service, and I'm very happy with the product, which is meeting all my requirements.

PROS: Good size/form factor. Great value if you D.I.Y. & can set up your own enclosure/project box/installation. Clear, legible screens, switchable (on/off) back light, all critical data to monitor circuits in one place, ideal for load management for emergency home backup generators, or similar applications, claimed internal overload protect circuit, monitor uses very low AC load, quality construction & look/feel. Data seems accurate when compared alongside digital multi meter. Back lighting & clarity of alpha-numeric characters is very clear & consistent: my photos do not do justice to the appearance of the screens to the naked eye. (They're nice). Very pleased, so far. Quality/longevity TBD.CONS: No UL listing, not for installations requiring NEC/home insurance approval (Such a capable monitor [with UL or other approvals] is not available anywhere @ this price point, however). No ground/earth circuit. Current Transformer wires could be a bit longer: as close as the CT’s were to my monitors, I still needed to extend all (4) of the CT leads with separately purchased wire. Accuracy is impacted if you exceed MFG max recommended wire length. Check w/ MFG, or search reviews - info is there. In typical USA residential applications (Single-phase, 2 x 120VAC ~ 240VAC), it is necessary to use (2) monitors to analyze the (2) 120v. lines coming into a typical service panel or load center panel. This requires you to do some basic math to combine the values from each monitor to assess Total system loads, etc. Not a big deal, but there seems to be a missed market in the USA for a single screen monitor with the capability to monitor (2) typical residential 120v. supply lines or "legs" on a residential utility service. Like I said, Very Happy - these are minor nit-picks/suggestions. Buy it - you'll be happy for the price!

The sensor was straight forward to install. I really liked the led back light with a button to turn on and off. Also liked the current core sensor can split and slide over to clamp on instead of having to remove the wire.Unfortunately, I wish the leads coming out of the sensor were longer. It’s a little strange to need 24V AC, but I hooked it up to the 24V transformer required to run the doorbell. Might need to purchase a 24V AC transformer for other specific applications. They pull so little current, I hooked them up to the same source.I bought two of these (one for each phase on my house) to see the independent loads. This will help once we have to use the generator to try to keep the loads balanced to obtain maximum life of the generator.All read outs and measurements seem accurate and the accumulation function works. I trust the other review comparing to a fluke device and that heavily impacted my purchase. Very happy.

Ordered 2 units and both arrived in good condition. Instructions are clear and easy to understand. Basically when looking at the gauges from the rear you install the Transformer clip ring into those 2 terminals at the top, order does not matter. The bottom 2 terminals is where you will power the unit with a standard 2 wire plug. The bottom of the two plugs is for the neutral wire of the plug which will be the left on the plug as plugged into a wall outlet. The right or 2nd terminal from the bottom you will attach the power wire from the plug cable which will be the right wire when viewing as plugged into a wall outlet.The Meters give good readings for watt, current, amps as well as frequency. I installed a pair on a backup generator and in order to measure readings from both legs of the power output I installed one on each leg exiting the generator (both Power Legs). The meters are of nice quality and are an excellent value for the money. I would recommend them and will purchase additional for future use.