Brymen BM 257 - safe enough to use on OZ 10amp 240v grid - Page 1
Forum section: electronics / testgear

author: chainsaw
author_rank: Contributor
timestamp: July 04, 2013, 01:35:03 pm
content: Would you consider the Brymen BM 257 safe enough to test the 240v grid considering its HRC fuse is only rated for 8 amps (Dave's Brymen multimeter short review). I want to take voltage measurements at different times throughout my Unit(s) power points to see the varying differences, just out of curiosity.Also want to test AA, AAA batteries as well as a Car battery & motorcycle battery as have 1 each essentially in storage which I charge up every month. Plus I want to check the ohm rating of a digital out cable for a CD player (it is supposed to be a true 75ohm cable) for accuracy. I can see the continuity testing as well as the electrical field detection being useful functions as well.

author: Monkeh
author_rank: Super Contributor
timestamp: July 04, 2013, 02:17:56 pm
content: The fuse isn't even in the circuit for voltage measurements.And yes, the HRC fuse is quite adequate anyway.No, you can't test cable characteristic impedance with a multimeter.

author: Lightages
author_rank: Unknown
timestamp: July 04, 2013, 05:12:13 pm
content: Would I use the BM257 to probe the wall sockets at 240V? Sure. Would I use it in the distribution panel? I think so. Would I use it on industrial electrical equipment, power feeds from the grid, or in power stations, no.....For anything almost any hobbyist would think of using a mulitmeter for, I think the BM257 is a very good and safe meter.As chainsaw said, you cannot measure the impedance of cables with a multimeter. Watch ths video by one of the forum members on how to do so.

author: chainsaw
author_rank: Contributor
timestamp: July 05, 2013, 02:01:50 am
content: Thanks guys for the reply & info.

author: IanB
author_rank: Super Contributor
timestamp: July 05, 2013, 02:37:06 am
content: As long as you are testing the mains in your house, then the biggest danger apart from electric shock is likely to be a loud bang, sparks and some smoke. If you make a short circuit then the circuit breaker will normally trip before anything too dramatic happens.If you have something badly constructed that overheats, then hopefully you are watching it and are within reach of the power switch or plug to disconnect it before it sets fire to anything.If you are uncertain of what you are doing it might be an idea to wear eye protection. Exploding devices may produce flying bits of shrapnel.But in general, measuring the mains with a meter set on the appropriate AC volts range (with the test leads plugged in the right sockets) is not likely to be a big risk.

author: chainsaw
author_rank: Contributor
timestamp: July 05, 2013, 03:55:26 am
content: Quote from: IanB on July 05, 2013, 02:37:06 am

author: ddavidebor
author_rank: Super Contributor
timestamp: July 05, 2013, 05:32:52 am
content: Simply, respect the cat ratings.If it's cat II 1000v, cat III 600v, cat IV 300v, follow it.

author: Bored@Work
author_rank: Super Contributor
timestamp: July 05, 2013, 02:42:08 pm
content: Quote from: ddavidebor on July 05, 2013, 05:32:52 amIt is worth to mention that Brymen is the only lesser brand multimeter that appear to tell the truth when it comes to the CAT ratings.From what we have heard they are serious about them and do test their meters for compliance with their ratings. While other manufacturers seem to slap any number on their meter to boost sales.

author: ddavidebor
author_rank: Super Contributor
timestamp: July 05, 2013, 03:14:40 pm
content: It's a brand you can trust on

author: Lucas
author_rank: Newbie
timestamp: October 07, 2013, 09:28:15 pm
content: Quote from: Bored@Work on July 05, 2013, 02:42:08 pmEven construction wise it's clear that this meter is much better thought through than most in its pricerange! Let's hope they keep following this track with their future meters