Anything special to look for when buying a multimeter?

[BoatingBeginner]

Hi folks

I need a new multimeter.

Are there any features to look out for which might come in handy - which are peculiar to the marine environment or marine electrics?

Cheers

BB

 

[elton]

Last time I bought a multimeter for the boat was about 3 years ago when they were 2 for £5 at Maplin. They're both still going strong, with the original batteries. Accurate and digital, they've done everything I've ever needed them to do, and at that price I wouldn't be upset if they took a soaking or got stood on. The same model is still available, but now at the vastly inflated price of £8.99.

Maplin's multimeter

 

[William_H]

Multimeter

I tend to agree with Elton price is the key factor to my mind.
A 20 amp current scale could be good compared to usual 10 Amp.
There are MM with lots of other features, mine measures frequency, inductance, capacitance and diode volt drop but most people wouldn't need these features.
If you buy 2 cheap ones you can make comparison so enhance accuracy. better still 3.
olewill

 

[Rigger Mortice]

If you buy 2 cheap ones you can make comparison so enhance accuracy. better still 3.
olewill

Agreed.
I thought mine were OK until I tested them against eachother. 3 meters all connected up to a supply at the same time. Useless.

 

[Ruffles]

I keep a cheap one on board but keep a 'proper' Fluke one at home as well. The latter has max and min recording which is very useful for finding poor connections or a failing battery under load.

But the cheap one is fine for everything else. And accuracy appears to match the Fluke exactly.

And the cheap multimeter was half the price of the replacement current fuse for the Fluke!

 

[noelex]

A clamp on multimeter (make sure it will measure DC current with the clamp) is very useful on a boat and will double as an ordinary multimeter.

The clamp on facility enables you to measure current in a wire without disconnecting it. It will also measure high currents in 12v wires and AC currents safely which a normal multimetrer will not do

 

[pteron]

Agree with the clamp recommendation - much damage to meter and electrizicals ensues from beginners with a standard meter on amps!

If you want the best, Fluke is the standard but way more expensive than the Maplin type.

 

[ProDave]

Being an (ex?) electronics engineer I have perhaps a different peception.

I have a (very old and battered now) Fluke 93. Expensive when new, but absolutely dependable, never lets me down, always accurate, batteries last literally years and years.

I also have a cheap multimeter. Batteries don't last very long, but my main complaint is when the batteries start getting low, it starts to give VERY inaccurate readings, but you have no warning that the readings are inaccurate. It's also very fiddly to replace the batteries, and in fact one of the screws have jammed, so next time the batteries go flat, it's in the bin, because it won't come apart to replace them short of breaking it. Somehow I just never trust it.

So as ever, you pay your money and take your choice.

I also have a cheap clamp on meter, bought mainly as a clamp on ammeter. the fact it also does volts, ohms etc via a pair of leads is a bonus. Perhaps if you just want a cheap meter, that's the sort of thing to go for.

But whenever I want to measure anything accurately with confidence, it's the Fluke I choose.

 

[All The Gear No Idea]

Coming from an electronics background, I have a Fluke and an AVO digital volt meter. They are both superb and have had them for many years now. They both cost a small fortune back in their day.

What is useful on both of these is the fuel gauge style meter underneath the digtal readout. This enables you to see rapid fluctuations in voltage, something a meter without this feature would not be able to show you. The AVO is particularly sensitive and refreshes almost as quick as an analogue meter.

A cheap meter is better than no meter, but like everything, you get what you pay for. If you know how to use a DV meter, then buy the best.

 

[BoatingBeginner]

Thanks chaps - may all be obvious for the more experienced, but your tips are pure gold for a numpty like me!

 

[Steve Clayton]

Coming from an electronics background, I have a Fluke and an AVO .......buy the best.

I know, I know; best of breed; just allow for parallax error!

 

[BruceDanforth]

I use a cheap £5 meter and it does the job. I've also connected up my handheld 'scope on occasion to try and work out why my Nasa depth sounder just flashes rubbish numbers when under way under engine but that remains a mystery as the supply was totally clean.

 

[ctva]

One of the main things that I use a MM on board for is continuity checking. If the meter has an audible signal for this, it is well worth it so you don't have to keep looking at the screen. I have this on my more expensive one where as the Maplin one I also have only displays on the screen.

 

[VicS]

Hi folks

I need a new multimeter.

Are there any features to look out for which might come in handy - which are peculiar to the marine environment or marine electrics?

Cheers

BB

If you need to ask that sort of question I'd suggest you do has I have done. Cheapies from Maplin.

Leave the Flukes and AVOs to the electronic technicians.

I promise you sooner or later you will do something silly ( like connect to a power supply with an amps range selected ) the fact that you toast a cheapie wont matter, no great loss, esp if you have the other half of a "two for the price of one" offer to fall back on.

The expensive ones may be better protected but still not immune to being wrecked.

I have wrecked my Digital AVO

 

[grumpy_o_g]

I know, I know; best of breed; just allow for parallax error!

Parallax error? That's what the mirror under the bands is for - if you can't see the reflection of the needle you can't get any parallax. The nice thing about AVO's of that era for me was that you knew what it was doing - you'd be told it was 20KOhms/Volt and what the voltage/current would be on the resistance scales so you could calculate errors. We used to use them a capacitor testers as well. Make sure you got the polarities round the right way and then measure the resistance across the capacitor. You'd expect it show low at first gradually increasing until it topped out at a certain value. If you'd bench-marked a known good capacitor first you could get the time it would take to reach a certain "resistance" and a get a pretty good idea of the health of the capacitor.

 

[john_morris_uk]

I know, I know; best of breed; just allow for parallax error!

That's an old model!

Mine looks like this:

I still use the cheap Maplins type on the boat though...

 

[Poignard]

Mine looks like this:

I've got one like that. Does yours have a little arrow on it?

 

[john_morris_uk]

I've got one like that. Does yours have a little arrow on it?

No! But the case is cracked and I wish I could find a new one. I could also do with some new leads and the 18v battery for the high resistance range.

I did get it serviced and calibrated when I was at RSRE Malvern though.

 

[Peter Martin]

Pontoon Boats

I would suggest you to go for the branded on which lets you the warranty for the particular period. and you have a safer side if it get damage during that period.

 

[Steve Clayton]

I've got one like that. Does yours have a little arrow on it?

Mine does; still using the green canvass tool bag that that was issued to me in 1969. (and it's as good as new).