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Can anyone recommend a good instruction/direction manual for ohm meters. I know little about them but they are supposed to be the cat's meow for electrical work. I want to find why some lights on a pontoon boat are not working. Thanks.
 

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Better to find book on basic electrical theory. Maybe a Chilton's or some kind of universal car "How to troubleshoot your car's electrical system" type of books...

You'll learn how the meter works by learning how electricity works.

All a meter does is measure voltage and resistance.

You need to know how those things work in order to be able to use the meter.


Good Luck..

John
 

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John is right on with his answer. First get something that will give you the very basic understanding of electrical circuits. Nothing fancy, just basic electrical 101. You have to have the minimum understanding of volts, current, and resistance, and how they interact.

Once you get that, you will be in the top 20% of people out there! Few have even the most basic understanding.

Without just a little understanding of how basic electrical circuits work, the meter won't be that much of a help. It may cause more confusion than understanding.

For anyone who has the basic knowledge, a decent Volt/Ohm meter is pretty much the first, and most necessary tool needed.
 

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I still have my Simpson 260 that my dad somehow got for me when I was just a kid...

We weren't well off and to this day I don't know how he got it.
Some friend of his brought it over and gave it to me.

Still works too...

John
 

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Too many engineers. Buy a $2.99 meter from Harbor Freight and read this

http://e-articles.info/e/a/title/Learn-to-troubleshoot-with-an-Ohm-meter.-Save-money-and-do-it-yourself!/

You want to find a broken wire in your lights, not build the space shuttle.
 

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jkersh1 said:
Too many engineers. Buy a $2.99 meter from Harbor Freight and read this

http://e-articles.info/e/a/title/Learn-to-troubleshoot-with-an-Ohm-meter.-Save-money-and-do-it-yourself!/

You want to find a broken wire in your lights, not build the space shuttle.
+1 on your link. It's a simple guide which most folks will understand. My Dad always carried a couple of lengths of wire, a battery and a light bulb (12v or 6v) which he would use to test a circuit, it's what I resort to if I'm in the middle of nowhere and need to check if a circuit is good. Don't work in every situation, but can be a life saver. Sometimes just having a spare piece of wire does the trick.

I now have a digital meter, but wish I still had the old anlogue ones we used in the military, can't beat that little kick you get on the needle when looking for a fault.
 

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To really over simplify how electricity travels; compare it to water.......the only difference is that to make electricity flow, the gate has to be closed, to make water flow, the gate has to be open.................... ;)
 

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Another thing to remember is that a couple of strands of wire can carry enough current to show the proper voltage on a digital meter, but won't be able to get your light to work. This can really confuse the trouble shooting. While having a meter and the understanding of how to use it can be helpful, a 12V bulb with a couple of wires hanging off of it is a good tool also.
 

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When troubleshooting simple circuits such as lights, I find a test light just as effective as a VOM.



Find them at sears or your auto supply.
 

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The August issue of the BMWMOA monthly issue of ON has a good article explaining basic DC circuits like you would typically find on a car, motorcycle or boat. It's written by Paul Glaves.
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dukey33 said:
When troubleshooting simple circuits such as lights, I find a test light just as effective as a VOM.



Find them at sears or your auto supply.
+1!

The very first weapon I grab when 12V gremlins start sneaking around.

To resolve problems I use it while chanting this:

"If you hear hoof beats don't go looking for zebras". :D
 

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budzee said:
I want to find why some lights on a pontoon boat are not working. Thanks.
having owned boats for almost as long as I have motorcycles.
I can tell you that 90% of all electrical problems on a boat are caused by corrosion and ground wires,
usually both at the same time.
 

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There are all kinds of tips and tricks to make electrical system diagnosis easy. It really isn't too difficult.

Check the simple stuff first - are all the fuses good? If you have a blown fuse, an easy way to find the short is to replace the fuse with a small bulb. The bulb will light up and act as a load on the circuit so you won't damage anything. Then start tracing wires from the fuse. When the bulb goes out, you've found your short.

Opens can either be on the supply (power) side, or the ground side. Use your voltmeter (I hate test lights) and connect the COM lead to the negative post of the battery. Then check for power at the load (in your case, the bulb socket). If you have no power, start tracing the wire back towards the fuse. You'll find your open when you have no power at point A, and power at point B. Open is between those points. If you do have power at the bulb, check for power at the ground side. No power = blown bulb. Power means you have a bad ground. Follow the ground wire. You'll find power at one point, no power further down. Open is between those points. If you have no opens in the wire, check where the ground attaches to the chassis. Often times it's just a loose or corroded ground terminal.

There are a lot more tricks, but those should help you find your problem. Oh, one of the reasons to connect COM to the battery neg post vs. the chassis is because if your chassis point is the problem, it will lead you in the wrong direction. Remember, the only true ground is the battery negative post!
 
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