Digital Multimeter

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Originally Posted By: Vikas
Originally Posted By: Donald
The OP was installing a remote starter so almost any DVM can measure 12V DC and ohms would be fine. He needs a "starter" DVM.

What he needs has nothing to with what he wants! How long have you been on BITOG? :-)


He does not know what he wants until he uses one for awhile.

I have been on BITOG a few 24 hrs.
 
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Originally Posted By: Donald
I have been on BITOG a few 24 hrs.

Ha, ha!! I had never thought that way before.
 
Originally Posted By: Donald
Originally Posted By: tom slick
I'm sure critic would be only be happy with this one:

http://buy1.snapon.com/catalog/item.asp?...amp;dir=catalog


The one for around $40 at HF also does temp, frequency. I have one, but I often use others. Th SNAP-ON one says it catches faster signals, but does not quantify that statement. If you want to catch fast signals, you need a scope.


But the one from HF misses some of critic's usual tool buying criteria:
It can't be from HF unless it is special circumstances.
It should be Snap-on and purchased on Ebay.
If it isn't Snap-on then it has to be equivalent and require much research and discussion.

That's pretty good criteria unless you are on a limited budget.


I have used a Extech meter that didn't sample fast enough for troubleshooting electronics in a CNC machine, a similar Fluke meter did. Sample rate can be a factor in troubleshooting beyond the basics. I don't think it would be a factor for most people troubleshooting their vehicle.
 
There are a lot of nice handheld digital storage scopes on the market now at very reasonable prices.

But OP asked about DMM's.
 
Are we talking about couple of hundred dollars or more? Even PC based (aka USB probes) seems to be more than that!
 
Originally Posted By: tom slick

I have used a Extech meter that didn't sample fast enough for troubleshooting electronics in a CNC machine, a similar Fluke meter did. Sample rate can be a factor in troubleshooting beyond the basics. I don't think it would be a factor for most people troubleshooting their vehicle.


I have noticed the same thing on the cheaper DMM's. Also seem to require a couple of these slow samples to settle on a stable signal.
 
I keep a Harbor Freight freebie multimeter in my glove compartment to check fuses or whatever. I have a Fluke 87, but only really get it out when I am testing a component that has to have a defined output rather than the normal Yes/No open circuit or 120/12V type of reading.

If all you are looking for is continuity or presence of a hot wire, go cheap.
 
Originally Posted By: tom slick
Originally Posted By: Donald
Originally Posted By: tom slick
I'm sure critic would be only be happy with this one:

http://buy1.snapon.com/catalog/item.asp?...amp;dir=catalog


The one for around $40 at HF also does temp, frequency. I have one, but I often use others. Th SNAP-ON one says it catches faster signals, but does not quantify that statement. If you want to catch fast signals, you need a scope.


But the one from HF misses some of critic's usual tool buying criteria:
It can't be from HF unless it is special circumstances.
It should be Snap-on and purchased on Ebay.
If it isn't Snap-on then it has to be equivalent and require much research and discussion.

That's pretty good criteria unless you are on a limited budget.


I have used a Extech meter that didn't sample fast enough for troubleshooting electronics in a CNC machine, a similar Fluke meter did. Sample rate can be a factor in troubleshooting beyond the basics. I don't think it would be a factor for most people troubleshooting their vehicle.


Very funny.
lol.gif


Thanks for the help guys. For the purposes of the remote starter install, it appears any basic DMM is going to do the job, so I'll probably just find one that is on-sale and make do with that. As my Prius ages, I'm sure the need for high-voltage related troubleshooting will arise at some point, so a CAT III 1000v capable DMM will probably be in my future...but not at this time.

Originally Posted By: Donald
Originally Posted By: Vikas
Originally Posted By: Donald
The OP was installing a remote starter so almost any DVM can measure 12V DC and ohms would be fine. He needs a "starter" DVM.

What he needs has nothing to with what he wants! How long have you been on BITOG? :-)


He does not know what he wants until he uses one for awhile.

I have been on BITOG a few 24 hrs.


That is unfortunately true (don't know what I want until I use it for a while).
 
If you can find a DVM with simulated analog scale with very fast response, you would be happy. I think that would rule out most of my HF type of suggestions!
 
Originally Posted By: The Critic
Originally Posted By: tom slick
Originally Posted By: Donald
Originally Posted By: tom slick
I'm sure critic would be only be happy with this one:

http://buy1.snapon.com/catalog/item.asp?...amp;dir=catalog


The one for around $40 at HF also does temp, frequency. I have one, but I often use others. Th SNAP-ON one says it catches faster signals, but does not quantify that statement. If you want to catch fast signals, you need a scope.


But the one from HF misses some of critic's usual tool buying criteria:
It can't be from HF unless it is special circumstances.
It should be Snap-on and purchased on Ebay.
If it isn't Snap-on then it has to be equivalent and require much research and discussion.

That's pretty good criteria unless you are on a limited budget.


I have used a Extech meter that didn't sample fast enough for troubleshooting electronics in a CNC machine, a similar Fluke meter did. Sample rate can be a factor in troubleshooting beyond the basics. I don't think it would be a factor for most people troubleshooting their vehicle.


Very funny.
lol.gif


Thanks for the help guys. For the purposes of the remote starter install, it appears any basic DMM is going to do the job, so I'll probably just find one that is on-sale and make do with that. As my Prius ages, I'm sure the need for high-voltage related troubleshooting will arise at some point, so a CAT III 1000v capable DMM will probably be in my future...but not at this time.

Originally Posted By: Donald
Originally Posted By: Vikas
Originally Posted By: Donald
The OP was installing a remote starter so almost any DVM can measure 12V DC and ohms would be fine. He needs a "starter" DVM.

What he needs has nothing to with what he wants! How long have you been on BITOG? :-)


He does not know what he wants until he uses one for awhile.

I have been on BITOG a few 24 hrs.


That is unfortunately true (don't know what I want until I use it for a while).


Not a bad thing. Learning about things is always a good experience. Get a cheap HF and consider it a throw-away. To start I might get one without auto-ranging. Or turn it off.

For example with ohms and auto-range if will measure the resistance of your body if you happen to be touching the leads. But on 0-100 ohms it would/could not.
 
I was helping a friend with a battery replacement, and for whatever reason he had two HF multimeters - identical ones, one yellow and one red. The ones that they give away for free or a few bucks.

One read 12.66V while the other read 12.92V on a battery. Could be VERY misleading, just think, the high reading one could show 12.6V when a battery is actually dying and only 12.3V. I didnt have my fluke which I "trust" (may be incorrect too, but I would trust it a bit more) to see which was right.
 
That is exactly what you do with a HF multimeter. You compare it with a Fluke and take some sample measurement. If they are in the ballpark, you keep it otherwise you mark your freebie as junk. But do an actual test before condemning it.

I have had two or three red ones and they matched the lab Fluke. The Fluke had extra digit though.
 
Again the OP was looking for +12 V or 0 V and ohms = 0 ohms or infinity. The cheapest HF should work.

I for one don't use any volt meter to test battery condition. A HF load tester is much better. And for whether a charging system is working, you are really looking for that increase in voltage by around 1.5V when the engine is started.
 
Originally Posted By: Donald
I for one don't use any volt meter to test battery condition.


So what about alkaline cells? Is that 0.3V on a 1.5V battery irrelevant too?

If the alternator you mention is only rising 1.2V but showing 1.5V would you then be worried?

I was very surprised personally to see such variability, even on the Chinese stuff.
 
Originally Posted By: JHZR2
Originally Posted By: Donald
I for one don't use any volt meter to test battery condition.


So what about alkaline cells? Is that 0.3V on a 1.5V battery irrelevant too?

If the alternator you mention is only rising 1.2V but showing 1.5V would you then be worried?

I was very surprised personally to see such variability, even on the Chinese stuff.


My main point was that just using the voltage of a flooded cell battery is not the best way to see if the battery is good or not.

Still for the OP, if the HF free one says 10 V or 14V thats good enough for him to know when there is voltage to a certain wire.
 
But it is so shortsighted to say that 10 or 14V to a wire is good enough. A multimeter is one of the most valuable tools in the toolbox, and having one with reasonable accuracy increases its value many-fold. There is far more even to battery health than just knowing if it can hold some load, one doesnt always want to test it in that manner.

A test light is the tool to just see if there is 10 or 14V on something.

A decent multimeter is an excellent tool. Those little HF ones are nice little tools, if they can be trusted. Great even for an in-car toolbox, since they are highly valuable for diagnosis in today's dummy light world. But .3V can mean the difference between a battery discharging and charging under operation. Was using a meter to watch the long term (cant do that with a carbon pile) loaded behavior, to get a misbehaving alternator that looks good under many conditions. 0.3V would change my assessment.

But end of the day, Critic has an interest in car repair, and is young. He will use a multimeter for MANY things for MANY, MANY years. he would be better suited to buy something with some capabilities that will suit him well in the long run, and have the accuracy and capability for lots of stuff going forward.

Actually, if I had to do it again and only buy ONE meter, Id buy a Fluke DC amp clamp multimeter. Ive found DC amp clamps to be insightful for troubleshooting on multiple things.
 
I still say start with a cheap one and learn a little and that one can then become the one you loan to people. Years ago I loaned someone one who checked with ohms across a 110V switch that was off, but with power to it. Wish I had loaned him a cheap one. I think it was my Heathkit with nixie tubes for a display.

While I do not have one in every vehicle, there is definitely always a working one in my 24' boat.

As far as a clamp on meter, while I agree they are handy, even more handy is a digital scope with clamp on probe. With it you can pull the fuse for fuel pump, connect clamp around battery cable, crank the starter and see which cylinder is bad as it will take less current than the rest while the starter is going.
 
Originally Posted By: Donald
As far as a clamp on meter, while I agree they are handy, even more handy is a digital scope with clamp on probe. With it you can pull the fuse for fuel pump, connect clamp around battery cable, crank the starter and see which cylinder is bad as it will take less current than the rest while the starter is going.



I would guess so, but what kindof $$$ are we talking about for that? A DC clamp is $$ enough.

Scopes I thought were on the order of thousands of dollars... May be wrong though.
 
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