400 Amp AC/DC Digital Clamp Meter, Auto-Ranging

For electricians that work on both high current alternating current and direct current this is a must as it can read amperage in both AC and DC up to 400 amps. It has a lower scale up to 40 amps. It is also capable of measuring voltage both AC and DC, resistance, micro current and impedance, temperature in Fahrenheit and frequency in hertz. The meter is lightweight, and all of the components are included in a high quality Klein bag. I would recommend this meter for electricians.

I chose this product for various reasons. If you live on a farm, you must deal with electric fences. I wanted something to check the current on each wire of the fence to insure cattle would stay in the property lines and stay out of my garden. It takes only a few minutes for cattle to cause havoc in any case. I do use it to check issues with electricity in my barn and house also. this item has multiple uses and is a welcome tool to my arsenal. It will work in many tool boxes because it is so versatile.

I work with various types of controls both AC and DC so I need a volt and amp meter to can work with both and have a decent range. The Klein CL390 filled all of these needs in one meter. The feature I like most about this meter is the 400 amp range for both AC and DC currents. After using this meter a while I also came to appreciate the NCV (non-contact voltage) built into the amp clamp. This is typical of most amp meters, but they are always ON or you have to go through menu settings to turn the NCV on ON/OFF. This is annoying, however, Klein has a dedicated button to operate the NCV feature. No annoying volt sensing alerts when using the meter for other functions. The Klein is feature rich with true auto ranging TRMS and Min/Max with data hold. The battery compartment is easy to access and takes standard AAA batteries. I also appreciate the test lead holder built onto the clamp. Too often I have difficulty getting the test leads in tight areas and keeping my hands a safe distance from energized circuits. The test lead holder helps keep me safe. The only drawback of this meter is using it outside with bright daylight. The reverse contrast is perfect in low lighting areas, but outdoors is difficult to see even with LCD backlight on bright setting. I still prefer the Klein reverse display over the standard LCD display of other meters. As for protection of the meter itself, there is nothing in the manual about fuse protection so I assume the meter could be destroyed if the wrong operation is performed; for example measuring high voltage on ohm setting. Overall, this is a really nice set. I don't use my volt meters for temperature measurement but I like that the kit comes with the thermocouple probe. I needed to use the temp probe once and compared it against a calibrated thermometer and the Klein probe was within a degree.

This tool is a volt and amp meter with a clamp/antenna for passive detection of any electricity. Auto ranging and has all levels to 400amp and 600 Volts. No contact sensor in the clamp and the meter claims to be safe dropped at 2 meters if you’re a dropper. Meet lots of industrial standards but I use it to find live wires. Comes with a case and a very basic thermocouple of limited quality. Detects temperature. C or F. Other type accessories are available for air and gas or surface or internal (needle) temperature probe. High contrast LCD readout is easy to see. Continuity test with included test leads. Instruction book is clear and comprehensive. The test leads are excellent quality.

I have owned a Klein CL2000 clamp meter for several years (and have been very happy with it), so I was curious about the improvements that have been made with this new model. After using it for a while, I am very impressed with pretty much everything about it. The new meter changed the selector switch so it can be operated with one thumb, whereas the older one was a 2-hand operation. As with the older meter, current can ONLY be measured with the clamp – do NOT try to measure current with the leads (except for 0-200 uA DC only). The new meter adds a 40 Amp scale so that if your current is < 40 amps you can have increased resolution. The older meter had 2 magnets for attaching to a metal case while doing measurements. The new meter has the option of a magnetic clamp, but there is a warning that doing DC current measurements with the magnetic clamp in position will negatively impact the accuracy of the current measurement. I would guess that this was an issue with the older meter also and that was why it was removed and made optional. The older meter’s leads had screw-on alligator clips for each lead, but the new meter does not have these, nor can the leads accept any screw-on attachment. I ordered some alligator clip probe adapters (get the ones for 2mm (.08”) probes if you order them also). Capacitance measurement is MUCH faster. The old meter took 23 seconds to measure a 3300 uF cap, while the new one took only 10 seconds; accuracy was the same for both. The new meter adds a temperature measurement as well as 2 levels of backlight brightness. Note that the meter can read to 1000 deg C, but the included probe is only rated to 230 deg C. Higher temperatures require a special metal probe that can withstand high temperatures

This is a fantastic multi-tool for electrical measurement. First it has a no contact voltage detector which is usually a separate tool. Next it has an auto range adjusting AC and DC volt meter with red and black probes, a second tool. The CL390 also has a clamp 40/400 AMP reader, in another tool. The tool also has a thermometer. Plus it can read Hz, resistance, continuity, dipole and more. So much function in one tool. As a home DIY, this is fantastic for me (see VIDEO) as I needed an AMP meter and my previous volt meter was stand alone. The unit is well made, solid. There are only 17 tiny pages of instructions in each language. In a regular sheet, maybe two. I made my own AC line splitter to validate the AMP reading was working. There are other functions such as min / max / max-min and averaging that are really useful, although above my usage grade. I try to stay in my limitations when it comes to electrical measurements and repairs. Overall, amazing product, well made. Good job Klein Tools.

I was very happy with the quality and build of the unit. And it's features. Seemed accurate. The main purpose of me buying the CL390 model is to measure DC amps with the clamp. The only deal breaker is... I bought this mainly to use at my sportsman club outside to measure DC amps coming from our 12v batteries. In the direct sun the negative contrast "easy to read display" is not readable at all. Even for my young eyes. I read other reviews that this was an issue, but I decided to try it for myself to see if it was that bad. Even when I turned the back light on full brightness. Indoors it looks lovely. Out in full sun it does not, unless you shade the display with your hand. My hands are both busy holding probes I don't have a third to shade the display. I returned it and bought the CL800 model instead. It costs more, but at least I can read that display in daylight and darkness with the back light on. I'm not sure why the CL390 is their only multi-meter in their lineup that has this negative contrast display. If it had the regular display like their other models I would have been happy. Long story short if you plan to use this outside. I'd look at the CL800 instead.

Klein makes great, professional products. This digital clamp meter is no exception. Fit and finish are terrific. The control knob is solid, the various ranges are comprehensive and the accuracy is spot on. And the display is brightly illuminated. Comes with a sturdy case, excellent leads and a temperature sensor probe. When using as a clamp meter, best to use the accessory plug that splits the line and common wires - you can’t measure amperage flow if you clamp both - the opposite flows cancel out. Great all around meter.

The Klein Tools AC/DC digital clamp meter with auto-ranging is well designed. Operation of the clamp is ergonomically formed to fit the hand easily. The dial for switching modes is placed so the thumb can easily roll up or down for quick changing. The screen for showing the readings of the meter is large enough to easily read. A nice feature not shown in the manual is the lead holder on the body of the unit allowing one hand to hold both the meter and the lead simultaneously.

The CL390 clamp meter measures both AC and DC current. Provides non-contact voltage detection, measures AC/DC voltage, DC microamps, resistance, provides audible continuity tracing, frequency, tests capacitance and diodes, measures temperature via a thermocouple probe, retains readings after shutoff. Take time to read the instructions and understand the functions provided. Features true root mean squared (TRMS) accuracy. The backlit digital display is easy to read. Auto-ranging reduces the need to adjust dial settings. The meter is powered by 3 AAA batteries (included). Auto-shutoff after about 10 minutes conserves battery life. Warranty: 2 years from date of purchase. Made in China.