Clamp meter

By vonash

Date 06-18-2004 22:00

Hey bridgedude. I thought you knew everything.

By brande

Date 06-19-2004 04:43

I use a fluke 29 with an auxiliary amp clamp (also a Fluke, 400 amp capacity)
If you use a Fluke or similar, learn to read the "bar graph" at the bottom of the window. It really lets you know what's going on.

Hope this helps

Good Luck
brande

By vonash

Date 06-20-2004 03:04

I really appreciate your post on an earlier subject. I have been doing things right so far, but I was way off base technically. After reading your response to my glib reply to that post I had to re-evaluate myself.
I guess that's why I spend my time with this forum. It is very informative.; A wealth of welding knowledge.
Best regards
Vonash

By thcqci

Date 06-21-2004 12:37

I have a Fluke 36 in my tool kit. Works well. Has built in multimeter in clamp meter. I have it calibrated locally every 2 years since it is not used often and it is in MY toolbox so I know how it is cared for. I went to get the the info from Fluke but it appears both the 29 & 36 are obsolete. Last link is to currently available Fluke clamp meters. The other 2 are links from Google to Fluke 29s & 36s. Can't go wrong with Fluke (costly but good) or other name brands. Hope that helps.

http://omnicontrols.com/lists/fluke4et.html

http://www.action-electronics.com/fl70.htm

http://www.fluke.com/products/sections.asp?AGID=3&SID=5

By jwright650 (*****)

Date 06-21-2004 12:42

Brande,
Does somebody make an amp clamp with a damper of some sort to stop the dancing needle?
John Wright

By MBSims

Date 06-21-2004 22:48

Miller used to make an in-line meter with LED gauges that used an RMS method to average the current/volts and either lock onto an average value or display continuous RMS values. You might check their website at millerwelds.com to see if they still sell it. Not a clamp-on meter, but it does filter out the fluctuations.

By DGXL

Date 06-21-2004 23:20

I use an EXTECH clamp meter that has a 2000 amp (AC/DC) range, voltmeter, ohmeter and 2000 degree F pyrometer.

I used to own several AMPROBE meters and one Fluke, the EXTECH was by far more accurate at calibration time than either one of the other two. Went through two AMPROBE's in one year as they are not very robust instruments - at $300 a pop plus the $50 calibration charge.

I checked into the Miller DM unit, it requires 120V power supply and has to be hard-wired into the welding circuit (e.g.: twist lock welding connectors). It does not use inductance to measure amperage.

EXTECH also sells their meter with a NIST certificate. All that, plus the acurracy, not bad for $250.00

www.extech.com

p.s.: This is an averaging-type meter, there are some fluctuations with changes in arc length, stick out, etc., but not like in my friends true-RMS meter which you also have to do some math to determine the average amperage.

By jwright650 (*****)

Date 06-22-2004 10:51

Marty, DGXL,
I use an AMPROBE (with the three different inserts, depending on the range needed). That needle is all over the place and I try to average it the best I can, but not exactly the results I was looking for. For the voltage I have been using a FLUKE multimeter and it does fine. I would like to convince my company that we need to get a amp clamp of some sort that has a steadier needle, but we have had this one for all these years and it gets us by. DGXL, you are right that meter is very fragile and won't take much in the way of rough treatment. I handle ours with lots of care each time I use it.
John Wright

edit: I told you all wrong, ours is "not" an AMPROBE amp clamp. I went and looked at it and it says Columbia Electric MFG on it.(Cleveland, OH)

By jwright650 (*****)

Date 06-22-2004 10:56

http://www.extech.com/instrument/clearance/Close-out.pdf
Here is what EXTECH had on their clearance rack. Looks like a deal to me. I might spring for one of these amp clamps for myself, if my company won't.
DGXL,
Thanks for the link to that site.
John Wright

By CHGuilford (****)

Date 06-22-2004 14:13

We use an Extech meter similar to the one shown in the link. We still get "readout bounce" but not so bad that we can't pick a number to use. Also Extech has fast turn-around on their calibration services.

Another meter that we have is a Remsco "suitcase" meter. It has analog
meters for volts and amps and seems to be dampened so the needles don't jump very much. The problem with that is that you have to insert the meter into the ground side of the circuit. Very cumbersome, so not good for quick checks and I don't like it for quarterly calibrations either. But it is very handy to set up and leave in place when running PQRs (AWS D1.5).

Chet Guilford

By brande

Date 06-26-2004 03:44

As far as digital meters go, dancing meters can be a problem. Over the years I have settled on the Fluke meters with the bar graph. Looking at the digits only can be confusing. Not only are your welding parameters changing constantly, but your meter's update rate is changing as well. Might be a place where an analog meter with a sweep needle might be more helpful.
Fluke gives us a bar graph on many models that can make reading much easier. Check them out. The bargraph Fluke has worked well for for quite a long time. (own 2 Model 29's and a Model 25).

Hope this helps

Good Luck

brande

By brande

Date 07-03-2004 04:54

A damper, I am not aware of. Spend some time reading the bar graph on the digital meter. It is very good when you get comfortable with it.
Real world welding involves joint preps that are not perfect, welders who are not perfect, wire chemistry that is not perfect, gas mix is not exact, and so on.

There are always some variables. The inspector (or responsible party) has to learn to deal with this.

My suggestion...

Put your meter on your welders often. Learn to interpret needle or bargraph swings-before the inspector arrives.

Remember-most all WPS's allow a range. We only need to average in this range-absolute exact numbers are usually not used.

Clear as mud....

Hope this helps

Good Luck

brande