question on clamp on electric meters

[burntside bob]

Does anyone have experience with the clamp on electric meters.
It is a voltage meter but instead of two wire leads the wire is encircled in a clamp that opens to enclose the wire.
I am thinking of purchasing one to use in finding electric problems when lights on the truck and trailer are out. This is instead of poking holes in the wire covering with the metal leads to see if there is a current present in the wire, which leads to future erosion of the wire and then problems.
Any one have experience with the clamp on meters in this application with truck current?
What make and model of clamp on meter do you have?
Would you recommend a clamp on meter to some one else to purchase?
Any comments on the performance or how to use the clamp on meters?

 

[k0ua]

You got me.. the only clamp on meters I have ever seen are to measure AC current. They do not measure voltage in the Clamp on mode. You put the clamp on around one wire to measure the current in Amperes flowing in that wire. I don't think there is anything to measure voltage by the clamp on method, and nothing for DC that I know of.

James K0UA

 

[kebo]

You are referring to clamp on current probes, which measure AC current not voltage. I'm pretty sure they do have some that will measure DC current too.

I think you are going about it the best way, just get a set of probes with some really sharp tips so that the hole you prick in the wire will be as small as need be. You can always put a small dab of silicone RTV over the hole, let it cure, then cover that with some electrical tape. There really isn't a better way to find breaks/bad connections in wires that I'm aware of.

 

[BrierPatch]

All the common clamp on meters I have seen are for measuring current. They do make them for AC and DC current, AC being the most common, you don't see the DC clamp on current meters very often. If it gets that teadious trying to find a problem and you are piercing the wires you can use a straight pin and it will make a smaller hole than a meter lead. There is also tapes and paints that you can seal the wires back up with to help prevent corrosion.

I did just remember that we got a whole bunch of milliamp clamp on current meters at work. They are for measuring 4-20ma current loops so you don't have to break the loop to measure the current in it. I haven't looked at one yet, but I assume they are for DC. They should be nice for working on analog control signals without disrupting the process. Of course this doesn't really help the OP's problem, but just got me thinking. By the way they are Fluke meters.

Here is a link to Flukes Website for them. http://www.fluke.com/Fluke/usen/Cla...mp-Process-Clamp-Meter.htm?PID=69415&trck=771

Good Luck

 

[crazyal]

As far as I know clamp meters are only for AC. If you are not worried about actual voltage they make a simple "light Pen" (at least that's what we call them at work) that a light inside it will glow when it's near AC.

Fluke 2AC VoltAlert, Voltage Detector, Non Contact Voltage Tester - Fluke

 

[fixit]

You can get a DC clamp meter but they are expensive as not many are made

and they aren't as simple to manufacture as an AC unit

i have one and they are good for the likes of finding out if your heater plugs are

ok and how many amps the altenator is charging at or starter motor is pulling

but for most Problems then you are looking to see if voltage is present or not and

they are no good for that

But i can see were you are coming from with not trying to poke holes in the insulation

I try my best not to as it is a weak spot for the future and worse than that it is one that your not looking for

 

[stevehart]

Clamp on amp meters are commonly available for AC and DC. They are quite inexpensive (Sears tools) and work great. I use one everyday in my work. But for voltage its another matter. If you must pierce the insulation, use liquid tape (3M product) or RTV silicone. The volt sticks discussed detect voltage usually over 50 volt; AC and DC so won't help much at 12 VDC.
Good luck. Be careful of the higher voltages!
Steve

 

[grsthegreat]

I've only seen one DC clamp on current meter in my 30 years as an electrician, and it wouldn't work in the range for automotive. Plus it was very expensive. They may make ones for automotive, but ive never seen one. Some meters state ac/dc, as does my Ideal brand meter. However under the specification page it lists AC current test only. It does dc voltage, just not current. Mind you, for $400 it SHOULD

The cheaper versions work only on AC current. Those yellow Fluke volt alerts pictured above work between 90-1000 Volts AC ONLY not dc.

When i work on my car/tractor i use the small probes and either push them under the connector or thru the insulation like everyone else. The whole time wishing i could be sitting on a beach in Hawaii.

 

[Bird]

Yep, my Extech AC/DC Digital Clamp Meter works on both, including automotive. I was a full time RVer when I bought it for $165 on April 21, 1990, to use on RVs. I rigged my own AC cord so I could check the amperage being drawn by an RV from RV Park hookups. And I used it to check alternator output in trucks, as well as battery drain in RVs. Mine also has a temperature probe. It's been very handy, and best I can tell, it's still quite reliable and accurate, although it isn't used much anymore.

 

[Sockwell]

As stated above, clamp on current meters are available for AC and DC systems. You get what you pay for. I have two such meters. One is an Ideal. It was about $125. The other is a Fluke (336, I believe). It was about $350. Both prices shown were from about 5 years ago.

We have machine control systems that use 24Vdc control systems and 4-20 mA valve actuators. The Ideal meter is good in most situations, but has trouble with the mA signals. Hence, the Fluke. If you know the amp loads to be 4 to 5 amps and up, the Ideal should be good.