Geekzone: technology news, blogs, forums
Welcome Guest.
You haven't logged in yet. If you don't have an account you can register now.

434 posts

Ultimate Geek
+1 received by user: 12
Inactive user

Topic # 112888 25-Dec-2012 23:31
Send private message

I have a dmm which says on the back .. this meter must not be connected to high energy sources which have transient voltages greater than 1000v. This includes 240v mains supply. 

What does that mean, how does it work explain it? 
I can understand if the meter cannot handle over 1000 volts but ..
a) What would happen if i connected it to more than 1000 volts 
b) Why does that include 240 volts mains supply ? or do they just say that to protect people who don't really know what they are doing

Create new topic
1221 posts

Uber Geek
+1 received by user: 143

  Reply # 737257 26-Dec-2012 02:41
Send private message

  a) Anything from nothing, to KABLAM and take off your fingers.
  b) Probably it's just C-Y-A, the 240v mains line could technically have a massive spike, but you'd hope not.

Edumacational material for you from the king of Multimeter teardowns, reviews and rants, Dave Jones: (blowing up meters with 4kv) (Dave ranting about a meter that blew up on 240v) (all about Input Protection)

James Sleeman
I sell lots of stuff for electronic enthusiasts...

1509 posts

Uber Geek
+1 received by user: 296

Lifetime subscriber

  Reply # 737280 26-Dec-2012 09:11
Send private message

because the insulation on the test leads and multimeter is only rated to 1000V above that and you start getting leakage voltage which will give you and electric shock


126 posts

Master Geek
+1 received by user: 6

  Reply # 737376 26-Dec-2012 14:55
Send private message

It appears the multimeter does not have sufficient protection to safely break high fault currents (such encountered with the AC mains), this means in worst case scenario, when internal protection device such as a fuse opens, there is risk of arcing, fire, and harm to user. If you plan on regularly using a multimeter, and going anywhere near the AC mains with it, buy a quality brand such as Fluke, they are expensive, but last almost forever. And, use the maker's own leads that came with it.
Otherwise, just keep the cheapie strictly for low voltage measurements.


9473 posts

Uber Geek
+1 received by user: 1380

  Reply # 737380 26-Dec-2012 15:17
Send private message

I bought a $20 cheapie a while back. Quality of the leads and probes absolutely awful. Measurement accuracy varies wildly depending on battery voltage and multiple other factors.

Decent ones start from round $100 at jaycar. Fluke are great but expensive for a general purpose model.

434 posts

Ultimate Geek
+1 received by user: 12
Inactive user

  Reply # 737414 26-Dec-2012 17:10
Send private message

cool thanks, i understand it now

Create new topic

Twitter »

Follow us to receive Twitter updates when new discussions are posted in our forums:

Follow us to receive Twitter updates when news items and blogs are posted in our frontpage:

Follow us to receive Twitter updates when tech item prices are listed in our price comparison site:

News »

Stuff Pix enters streaming video market
Posted 21-Mar-2018 09:18

Windows no longer Microsoft’s main focus
Posted 13-Mar-2018 07:47

Why phone makers are obsessed with cameras
Posted 11-Mar-2018 12:25

New Zealand Adopts International Open Data Charter
Posted 3-Mar-2018 12:48

Shipments tumble as NZ phone upgrades slow
Posted 2-Mar-2018 11:48

Oppo R11s: high-end Android, budget price
Posted 27-Feb-2018 16:27

Samsung New Zealand introducing the Galaxy S9 and S9+
Posted 26-Feb-2018 07:00

Fujifilm X beats its best with new top of the range, high-performance camera
Posted 24-Feb-2018 14:05

One million kiwis affected by cybercrime
Posted 24-Feb-2018 13:58

New Zealanders want to engage with government online and via mobile apps
Posted 24-Feb-2018 13:56

Samsung launches Samsung Max
Posted 24-Feb-2018 13:52

CPTPP text and National Interest Analysis released for public scrutiny
Posted 21-Feb-2018 19:43

Foodstuffs to trial digitised shopping trolleys
Posted 21-Feb-2018 18:27

2018: The year of zero-login, smart cars & the biometrics of things
Posted 21-Feb-2018 18:25

Intel reimagines data centre storage with new 3D NAND SSDs
Posted 16-Feb-2018 15:21

Geekzone Live »

Try automatic live updates from Geekzone directly in your browser, without refreshing the page, with Geekzone Live now.

Are you subscribed to our RSS feed? You can download the latest headlines and summaries from our stories directly to your computer or smartphone by using a feed reader.

Alternatively, you can receive a daily email with Geekzone updates.