Digital Multimeter With DC Clamp On

How about installing low resistance shunts, measuring voltages across them with a basic multimeter, and calculating the currents?

I installed many panels as a roof, under which I can easily measure.

I hope to bring also the myth down that nothing grows underneath, since our vegetable garden will be there.

The inverters are 400 feet away and 2 conductors of 10 AWG gave me 2.7 Volts voltage drop.

At 20 Amps, 48 Volts DC. I am now using 1/0 because of the distance. These drops are expensive and bring the efficiency down a lot, so do extra series shunts.

With a clamp on device (with Hall effect) I can quickly check the amps per string and also with the solar connectors it is easy to disconnect each panel, short it (since they come with a male and female, minus and plus) by just connecting the + to the minus.

I found one at Sears for $53.99 but do not know if it is good. Extech has one for about $129.00 but I would really have some feedback from users.

There is an ocean between me and Sears and traveling abroad is very expensive. I cannot afford to buy, check it and bring it back (Sears warranty) if I am not happy with it. Extech has more return restrictions.

Probably there are lots more makes, like Fluke (out of budget).

I have a system that uses one pilot inverter to charge batteries (only 300Ah@12 Volts) that can supply 120 volts AC/60 Hz. This pilot becomes the reference for all the grid tie inverters when we have a power failure. So in off grid state, the grid tie inverters become suppliers for everything more than 500 Watts.

This saves thousands for batteries that I do not need. (at night I am messed up off course, but then I usually sleep)

I made strings of 48-100 Volts (the long runs), close to grid parallel 12 Volts 250 Watts circuits and a 375 Watts/12 volts long run for the off grid(battery) inverter.

When everything is finished, I will send a picture.

I bought one at Sears as well. Be careful they have two models, one that does AC only and one that will do AC and DC. They look very similar.

I have yet to use it for anything significant. I tested the DC Amps using a lab supply and a multimeter. It appears to be accurate. At least close to my Fluke. I intend to use it to check my solar array as well, that is, the array that I'm still working on installing.

I read some reviews on the model I bought that weren't positive, but I bought it anyway. We'll see.

Something like UT203 is OK for amateur use. Just don't put it's protection features under test. S.M.

it's its

May( )be S.M.

English is not my native language as you can tell, but on this I thought it went like: John-John's, It-It's, not "is", not "has". In my language nouns and their pronouns are interchangeable. Thanks. S.M.

That is one of the quirks of English.

Apostrophes are used for contractions and for possessives of nouns, but not generally for plurals and not for possessives of the personal pronouns.

At first it takes conscious attention to sort this out properly, but with care and experience it can become second nature.

--Editor Crankshaft

Thanks. Any idea of the price? Looks like the circuitry of the Sears (same steps)

Saw it advertised for approx. $35.00.

If you already have a multi-meter you could just get a current transducer for it.

I have plenty of multi-meters, dating from the age of the "flintstones" up to some modern stuff, but DC current with a clamp is not one of it.

If these transducers are clamp on, I get even a lot more expansion for possibilities and can put several pieces in the system. The outputs I can log or read with a multiplexer (and maybe LabView?)

Thanks.D

Yes they are clamp on. Many manufactures of multi-meters will make one mine an Amprobe CT-600 will read up to 600 amps AC or DC. You may find that one of the manufactures of the new multi-meters you have make one. Just use the output port from it.

Try this cheap little beauty.

This does about what the Sears does also. I guess they both come from Shenzhen.

The UT203 has no temp probe but is $20.00 cheaper. This advertised clamp on meter cost the same what Sears sells it for without promotion. I think I try the Sears because of the service. (warranty) GA, thanks

Be careful! Some clamp-on meters act as current transformers. These will ONLY measure AC current.

The only ones I know that measure DC current use a Hall sensor.

Unless it specifically says it measures DC current, it probably does not! I saw no mention of DC in the Radio Shack ad.

Read more carefully. The ad mentions DC current before it mentions AC current in the specification section.

I just read the user's manual for that unit and it says it does DCamps, so it must.

Looks good in the picture.....

At that price it's an excellent disposable meter.

Just in case, I was referring to the link of post #12, which points to a Radio shack ad. I still see no mention of DC in the ad. It just says true RMS. The true RMS of DC is zero.

I did look at the manual, and yes, it does measure DC, but there is nothing in the ad that that says so.

OK, this is a copy and paste of the third (3rd) bullet down in the "check it out" section of the ad: DC current 40.00A/400.0A/800A; AC current 40.00A/400.0A/800A True RMS

Hint: scroll down a little in the ad.

OK, I stand corrected!

I did scroll down a little, but as soon as I saw:

I assumed I had seen the entire ad. Now that I did scroll down farther, it does indeed look pretty good for the price! To me it sure is a strange layout for the ad...

I have 3 DC clamp meters

The Fluke died and will stay that way.

The two that still work....

Lutron CM9940 is a tough unit measures up to 600ADC. Cost approx USD150

Kyoritsu KEW MATE MODEL 2001has a very handy small open head that is easy to slip onto conductors in cramped situations. Measures upto 100ADC. Cost approx USD150.

These instruments earn their keep. New batteries is all they ask for.

Taiwanese instruments and tools have a good price/quality break.

IMO those $50 instruments are too cheap to be "good".

I have a $300.00 Fluke that measures up to 600ADC and the "cheap" RS model that measures up to 800ADC. Cheap has more functions than Fluke.

Cheap trumps Fluke all day.

I like cheap.

You can get a calibration certificate for a Fluke.

If this is not required then I agree. Cheap is good.

That is really cheap. How long has it been satisfying you?

I've had it over a year and have had no issues.

But I haven't dropped it yet either.

So long as it's not made from recycled VHS video cassette cases (like the stuff inside Korean cars) it should be right.