Extech 330 Multimeter safe for checking mains voltage?

[Merry Prankster]

Hi everyone.

I'm about to replace our old electric shower and want to ensure that I have shut off power to the curcuit before I touch any wires. I was considering buying the Fluke T90 Voltage and Continuity Tester for this purpose, but I can get the Extech 330 multimeter for the same price, which obviously provides much more functionality - albeit with a reduction in quality. Is the latter safe to use on mains voltage?

Cheers for any help.

 

[endecotp]

I've never seen a multimeter that wasn't "safe" for mains voltages, for some definition of "safe".

 

[ericmark]

In most multi-meters are OK for mains voltage however often the leads provided with them are not. GU38 I seem to remember is the general guidance given for leads for use with multi-meters and as a result they are sold as GU38 test leads. They have fuses built in, bits to stop finger slipping down the lead, and the metal showing is very limited. For some work they are a real pain for example the only way to get the leads into a socket is with a special adaptor as tips are too small.

The standard voltage tester for proving dead is already fitted with GU38 type probes and does not require a battery so battery can't become flat and has no selector switch so can't be set to wrong range. Even so you should use a proving unit with them. Proving units should have 50 volt output to prove that with any voltage within the low voltage range the tester being proved will work. However many have an output of 500 volt to light all test lamps this is rather silly as because a tester works on 500 volt does not mean it will work with 50 volt. Some do test each voltage in turn but not all.

In all the jobs I have done only ICI at Rocksavage required me to use a proving unit. It was instant dismissal if you were found without the voltage tester and proving unit at your side. Yet the proving unit was 500 volt so near useless to show tester will work on 50 volt AC or 75 volt DC.

Personally with a shower I would turn off isolator and all MCB's and use just a cheap voltage tester the type you can test by rubbing on your jumper. Yes that's wrong but buying all that equipment for one shower is really going OTT.

 

[Merry Prankster]

Personally with a shower I would turn off isolator and all MCB's and use just a cheap voltage tester the type you can test by rubbing on your jumper. Yes that's wrong but buying all that equipment for one shower is really going OTT.

Cheers for the reply. I'm planning to start learning electronics soon so I need to get a multimeter anyway, so the Extech is probably the best option.

 

[westie101]

The make can vary if you want but make sure that both leads have got fuses at the remote test end, not the meter ends

Like this

http://uk.rs-online.com/web/p/multimeter-test-leads/0204583/

Also go for a high accuracy AC type, we often are attending voltage complaint issues where they can be over 5 volts innacurate

 

[Spark123]

I think the document which is referred to above is GS38.
As with most things, how safe anything is depends on the user. If you are using it to detect presence of voltage and you set it wrong it may show zero volts on a live circuit. For voltage detection, GS38 recommends using a voltage indicator such as the T90.
I've not come across Extech before so don't know about their quality, as far as multimeters go I tend to stick with what I know such as fluke.

 

[ban-all-sheds]

I can get the Extech 330 multimeter for the same price, which obviously provides much more functionality

But do you actually need the extra functionality?

Will you really want to use it to measure capacitance, frequency, or temperature?

 

[JohnW2]

But do you actually need the extra functionality? Will you really want to use it to measure capacitance, frequency, or temperature?

Maybe not temperature, but probably resistance and current, as well as possibly capacitance and frequency, and maybe other things ....

I'm planning to start learning electronics soon so I need to get a multimeter anyway...

Kind Regards, John

 

[ban-all-sheds]

For electronics use I cannot think of a single reason why a multimeter would be preferable for measuring capacitance, for example, to a proper capacitance meter/tester.

 

[JohnW2]

For electronics use I cannot think of a single reason why a multimeter would be preferable for measuring capacitance, for example, to a proper capacitance meter/tester.

That's not the choice which was being made - it was between a Fluke 'voltage and continuity tester' and a multimeter. I think it's pretty obvious which of those would be more useful in relation to electronics!

Kind Regards, John

 

[ban-all-sheds]

It was being used to justify getting the Extech 330 instead of the FLuke T90.

But if the reason for wanting the extra functionality is not a valid one.....

 

[JohnW2]

It was being used to justify getting the Extech 330 instead of the FLuke T90.

Indeed.

But if the reason for wanting the extra functionality is not a valid one.....

I'm a bit lost. The T90 does not measure voltage (other than with an LED ladder), current or resistance (other than a 'continuity beeper'). Is it not glaringly apparent that someone with an interest in electronics has a "valid reason" for wanting more functionality than that?

Kind Regards, John

 

[ban-all-sheds]

It is glaringly apparent that such a person has such a valid reason for wanting more functionality.

It is far from glaringly apparent that the appropriate way to provide additional functionality such as capacitance measurement is via a cheap multimeter.

 

[endecotp]

For electronics use I cannot think of a single reason why a multimeter would be preferable for measuring capacitance, for example, to a proper capacitance meter/tester.

Cost.

 

[ban-all-sheds]

Well let's all just start buying the cheapest tools and materials we can find then.