I think you can also loop the wire through clamp twice and then do the sums to calculate correct reading.

Alistair

> On Jan 8, 2017, at 2:46 PM, David Beierl <dbeierl@ATTGLOBAL.NET> wrote:
> 
> DC clamp meters use Hall-effect sensors to measure the magnetic field
> surrounding the clamped wire.  They can be fooled by any static magnetic
> field, but have a zero button to eliminate residual readings.  Ideally they
> should be zeroed in the exact measuring position with wire already
> clamped.  Altering the angle or position in any way can cause a different
> false reading to appear.
> 
> On Sun, Jan 8, 2017 at 5:42 PM, Dennis Haynes <d23haynes57@hotmail.com>
> wrote:
> 
>> Yes!
>> 
>> Dennis
>> 
>> 
>> From: Ralph Meyermann [mailto:ralphmeyermann@gmail.com]
>> Sent: Sunday, January 8, 2017 5:28 PM
>> To: Dennis Haynes <d23haynes57@hotmail.com>
>> Cc: vanagon@GERRY.VANAGON.COM
>> Subject: Re: Multi meters, Was Dang Headlights.
>> 
>> As long at the right meter/amp clamp is used!
>> 
>> On Jan 8, 2017 3:31 PM, "Dennis Haynes" <d23haynes57@hotmail.com<mailto:
>> d23haynes57@hotmail.com>> wrote:
>> The MS2108A meter has both AC and DC current capability with the clamp on.
>> AC is easier to measure this way due to the constantly changing current
>> basically making a small transformer. For sensing DC this way the meter has
>> to rely on the one time change.
>> 
>> Dennis
>> 
>> 
>> From: Ralph Meyermann [mailto:ralphmeyermann@gmail.com<mailto:
>> ralphmeyermann@gmail.com>]
>> Sent: Sunday, January 8, 2017 4:26 PM
>> To: Dennis Haynes <d23haynes57@hotmail.com<mailto:d23haynes57@hotmail.com
>>>> 
>> Cc: vanagon@GERRY.VANAGON.COM<mailto:vanagon@GERRY.VANAGON.COM>
>> Subject: Re: Multi meters, Was Dang Headlights.
>> 
>> Depending on meter, some prefer AC current. I think but not sure DC
>> current is usually connected in the current path to read?
>> 
>> On Jan 8, 2017 3:23 PM, "Dennis Haynes" <d23haynes57@hotmail.com<mailto:
>> d23haynes57@hotmail.com><mailto:d23haynes57@hotmail.com<mailto:
>> d23haynes57@hotmail.com>>> wrote:
>> This meter has both a 40 and 400 Amp range. Measuring small DC currents
>> with a clamp on meter can be a bit challenging. This meter seems to work ok
>> for small currents down to about an amp but I wouldn't use it as my first
>> choice say for finding small battery drains.
>> 
>> Dennis
>> 
>> 
>> 
>> -----Original Message-----
>> From: Steve Williams [mailto:steve@williamsitconsulting.com<mailto:steve@
>> williamsitconsulting.com><mailto:steve@williamsitconsulting.com<mailto:
>> steve@williamsitconsulting.com>>]
>> Sent: Sunday, January 8, 2017 1:03 PM
>> To: Dennis Haynes <d23haynes57@HOTMAIL.COM<mailto:d23haynes57@HOTMAIL.COM
>>> <mailto:d23haynes57@HOTMAIL.COM<mailto:d23haynes57@HOTMAIL.COM>>>;
>> vanagon@gerry.vanagon.com<mailto:vanagon@gerry.vanagon.com><mailto:
>> vanagon@gerry.vanagon.com<mailto:vanagon@gerry.vanagon.com>>
>> Subject: Re: Multi meters, Was Dang Headlights.
>> 
>> Hi Dennis,
>> 
>> Thanks for the information and the link.  I have a $20 Radio Shack (is
>> that dating myself?) meter in my tool box.  The lack of the ability to
>> measure current is real frustrating with it.
>> 
>> The meter that you specify, what is the smallest current that it can
>> accurately pick up with the inductive clamp?  I've never used one.
>> 
>> Thanks again!
>> 
>> Cheers,
>> Steve Williams
>> 
>>> On 06/01/2017 10:51 PM, Dennis Haynes wrote:
>>> So here we are in the New Year and Friday is over. I'd like to try doing
>> something a little bit different. When a thread comes up I will try to
>> offer some type of enlightenment to get us thinking of a better or
>> different way. Let's raise the bar! So here is a safety thought for meters.
>>> 
>>> Inexpensive meters have their place. Most of the time when something is
>> not working we just need to know if the power is on or if there is
>> continuity. Heck  often still reach for a test lamp. Accuracy is not a
>> concern for many diagnostic needs.
>>> 
>>> But there is another consideration, safety. Of course we should be
>> wearing eye protection when working with electricity, especially around
>> batteries. At some point we will use a meter incorrectly either because we
>> don't know what we are doing or we make a mistake. Maybe we are testing for
>> resistance and place the leads across a voltage source instead. For 12
>> volts this usually is not an issue. Although if use the ammeter function
>> and we connect across  battery there is hope that the fuse will open, and
>> fast enough to prevent some mishap. Also, at some point you know you will
>> try to use the same meter for a 120 volt AC circuit or maybe you are at a
>> campground that even has 240 VAC at the power pole. Even using a meter
>> properly one could be exposed to a high voltage spike or surge that could
>> overcome the insulation capabilities of the meter or leads.
>>> 
>>> Meter are now also rated for protection levels. Here is some information.
>>> http://support.fluke.com/find-sales/download/asset/1263690_6116_eng_h_
>>> w.pdf
>>> 
>>> As for features of late I have mentioned getting a meter with a clamp on
>> ammeter. Also, having a bar graph display is really helpful when trying to
>> observe a vary condition such as the O2 sensor. Most bar graphs will update
>> multiple times per second, much faster than a numeric display.
>>> 
>>> Here is a meter I purchased from Amazon back in June. It usually goes
>> for ~$40. It has both AC and DC ammeter capability up to 400 amps and it
>> has a bar graph display. It has a hold function so you can catch a reading
>> such as testing the starter. Even nicer is that this economy meter is rated
>> for Category 3 protection.
>>> 
>>> MS2108A Auto Range Digital Clamp Meter 400 AC DC Current Hz Tester
>>> 
>>> This meter is now my travel meter and I'll be getting another one.
>>> 
>>> Dennis
>>