OHM Volt meter

Thedreamoneday

Thedreamoneday

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I'm looking to boost my knowledge in all things boaty and one area I'm wanting to dip my toe in is electronics and with that in mind I want a Voltmeter, is there anything I should really be looking for or will a £7 eBay special do everything that's needed- I've never looked at them before but just thought they'd be more expensive than that.

Thanks
 
The cheap ones are reasonably OK, there will probably be areas like over-voltage protection isn't anywhere near as good as a pro meter. I have come across one unit that was fairly inaccurate, probably quite rare but it's worth comparing the meter with a known good one before using for anything serious if you can.
 
Thanks, I don't mind spending an extra fee ££'s getting a decent one as it's one of those things that you'd probably only ever buy one but don't see the point of wasting ££'s if I don't need to.

Any recommendations of a decent make?

Cheers
 
I have cheap ones like the yellow £5 sort.
I also have Fluke and Isotech ones.
The cheap ones I don't mind lending to people, taking on boats or using in the rain. They are great.
They get through more batteries because they don't auto-off
The expensive ones are only a little more accurate, have autoranging etc. I don't lend those out for people to not look after.
I would not advise spending a lot at first. Keep the cash for when you want a DC clamp ammeter or something.
 
The cheap ones are **** and a waste of money. Inaccurate, poor protection, the circuit boards rot.

Maplins UNI-T range are just about acceptable. You only need a basic tool with AC volts ( to 400 Vac ) DC Volts, resistance and a good current rating ( 10 amps minimum ) A continuity buzzer is possibly the handiest setting! A unit with an optional plug in clamp meter attachment will get some use occasionally and a thermometer probe can be handy.

Autoranging is useful as is peak reading hold.

I have a Fluke 77 that has lasted me 30+ years already.
 
Thedreamoneday said:
I'm looking to boost my knowledge in all things boaty and one area I'm wanting to dip my toe in is electronics and with that in mind I want a Voltmeter, is there anything I should really be looking for or will a £7 eBay special do everything that's needed- I've never looked at them before but just thought they'd be more expensive than that.

Thanks
Click to expand...

I bought a cheap digital multimeter ( £5) from Maplin and later 2 more on a "2 for 1" offer.

I keep one at home, one on the boat and gave one to my son.

More than adequate for a novice. Although the leads were not so good on the first one.

Sooner or later you will burn it out and at that price its no serious loss, like wise if you drop it overboard.

This is the one I bought ( has a protective holster and a bit more expensive now )

http://www.maplin.co.uk/p/domestic-multimeter-n20ax
domestic-multimeter.jpg
 
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Buy yourself a decent set of leads with pull-off croc clips that are large enough to go onto battery lugs and large bolts. These will probably cost you three times as much as a cheap meter!!!!
 
sailinglegend420 said:
Buy yourself a decent set of leads with pull-off croc clips that are large enough to go onto battery lugs and large bolts. These will probably cost you three times as much as a cheap meter!!!!
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I did and you are right they cost several times as much as the meter...... but mostly I use a pair, much longer than standard, made up with a pair of banana plugs, "extra flexible" wire and a pair of croc clips
 
sailinglegend420 said:
Buy yourself a decent set of leads with pull-off croc clips that are large enough to go onto battery lugs and large bolts. These will probably cost you three times as much as a cheap meter!!!!
Click to expand...

Leads are important. Flimsy ones will fail at the strain relief at the meter end. They are not interchangeable generally. Maplin are pretty good and you can see what you are buying. Auto off is good, and so is the gimmick of a dial that illuminates automatically in the dark.
 
With a cheap Voltmeter you can check 12 Vot DC and 220 Volt AC.
But if you want to check the insatllation of a SSB Radio which needs up to 40 Amps, I would recomend a MilliOhmMeter.
Its a 4 wire measurement and you can read out for example a Resistance in the cable to and from the battery of e.g. 25MilliOhm.
Such a low Resistance produces a Voltage drop of 1 Volt, which is high in comparison to the 12 Volt of the battery.
Greetings, Willy
---
I am involved with marine radios, I give SRC Kurs in Hamburg
 
VicS said:
Sooner or later you will burn it out and at that price its no serious loss, like wise if you drop it overboard.
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I have two of those. One at home and one on the boat. Four or five years old.

They read exactly the same as my Fluke. They are also half the price the replacement current fuse on the Fluke!

The only time I use the Fluke is for the MAX/MIN facility.

A useful extra is a 100 ohm resistor to connect across the leads when checking for 12v.
 
nigelmercier said:
Why?
Click to expand...

So that there is some current draw. Otherwise you can get apparently good readings even though there is bad connection somewhere ( Got the Tee shirt!)

I reckon a lower resistance than 100ohms is needed.

Often, for this reason, better to use a bulb on a couple of leads rather than a meter.
 
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