FLUKE 87V Ex True RMS Multimeter - Page 1
Forum section: electronics / general

author: ErikTheNorwegian
author_rank: Frequent Contributor
timestamp: December 28, 2011, 03:02:34 pm
content: Just

author: 0xdeadbeef
author_rank: Super Contributor
timestamp: December 28, 2011, 04:22:16 pm
content: The Ex is the "intrinsically safe" version of the 87V:http://www.fluke.com/fluke/usen/fluke-87v-ex.htm?PID=56141

author: samgab
author_rank: Frequent Contributor
timestamp: December 29, 2011, 12:07:32 am
content: Quote from: ErikTheNorwegian on December 28, 2011, 08:11:26 pmI still get your question though. Have they actually CHANGED anything to make it "intrinsically safe"? The orange rubber is less likely to ignite or auto-combust than yellow rubber?I understand that the EX model is rated to not to cause explosions, and if I worked in an explosive atmosphere I'd definitely spend the extra money, but I wonder if the regular 87V is just as safe but just doesn't have the EX rating attached. Maybe it has special fuses? Or a special zener clamping diode? I'm curious.EDIT: Oh, and nice purchase, by the way.

author: Unknown
author_rank: Unknown
timestamp: December 29, 2011, 12:20:10 am
content: Lower voltages across switch contacts to reduce arching maybe? Special switch contacts? No/different spark gaps? I would expect some hardware modifications, since it seems silly to design the regular 87V to meet EX standards.

author: samgab
author_rank: Frequent Contributor
timestamp: December 29, 2011, 02:02:27 am
content: Quote from: ErikTheNorwegian on December 29, 2011, 01:06:14 amWow that is an amazing buy at that price then! Yeah, a teardown would be interesting. I wonder if there is anything obvious visibly different inside...

author: robrenz
author_rank: Super Contributor
timestamp: December 30, 2011, 12:11:57 am
content: No pictures attached

author: samgab
author_rank: Frequent Contributor
timestamp: December 30, 2011, 12:14:30 am
content: Quote from: robrenz on December 30, 2011, 12:11:57 amFrom his wording, I got the impression that it is still en route to him.

author: Short Circuit
author_rank: Frequent Contributor
timestamp: December 30, 2011, 01:10:45 am
content: I believe the only difference is in the color of the sleeve.'Problem' with Atex(95) is that each product must be certifiedindividually, which makes it so expensive.

author: samgab
author_rank: Frequent Contributor
timestamp: December 31, 2011, 12:49:30 am
content: Quote from: ErikTheNorwegian on December 30, 2011, 06:39:28 pmMaybe that's what someone's done with your incoming "EX"...

author: wkb
author_rank: Super Contributor
timestamp: December 31, 2011, 01:21:28 pm
content: Quote from: ErikTheNorwegian on December 30, 2011, 06:39:28 pmJust don't take that badge-engineered Fluke out to a location where Ex really matters.That could easily qualify you for a Darwin Award (http://www.darwinawards.com/

author: Fraser
author_rank: Super Contributor
timestamp: January 03, 2012, 09:51:13 pm
content: I have seen inside a Fluke 87 III EX model and can advise that there is more to it than changing the colour and testing etc.The 4mm terminals and parts of the PCB are encased in an epoxy material making the meter almost impossible to repair if you kill it. The whole thing is built from the perspective of being safe in an explosive gas atmosphere. It's gasketted and basically airtight when in use. I suggest you don't try to open it if you need the EX rating. In terms of ownership, its a great meter, BUT it is less serviceable than a standard model because of the epoxy coating on the PCB and around the terminals. You can't even fit new 4mm sockets if they get worn.Hope this helps

author: samgab
author_rank: Frequent Contributor
timestamp: January 03, 2012, 11:21:00 pm
content: Quote from: Aurora on January 03, 2012, 09:51:13 pmOh, of course, that makes sense. Coat all of the internal components with epoxy resin so there is absolutely no chance of a spark jumping from anywhere to anywhere, therefore making it impossible to start an explosion with it.

author: IanB
author_rank: Super Contributor
timestamp: January 03, 2012, 11:36:06 pm
content: Quote from: samgab on January 03, 2012, 11:21:00 pmBut what if you make a spark when you touch the probes to a circuit?

author: Fraser
author_rank: Super Contributor
timestamp: January 03, 2012, 11:47:30 pm
content: BANG !

author: samgab
author_rank: Frequent Contributor
timestamp: January 04, 2012, 01:52:12 am
content: Quote from: IanB on January 03, 2012, 11:36:06 pmlol, yeah I thought of that. But if that happened it wouldn't be the fault of the EX meter, it would be the user's fault.So the meter would still be "EX"... and the user would be dead.

author: Wartex
author_rank: Frequent Contributor
timestamp: January 04, 2012, 04:15:17 am
content: I don't know about DMM but some Ex flashlights contain inhibitors to prevent explosive gas mixture from forming by binding some of the gas molecules. Also they don't use copper on contacts to prevent sparks.

author: ipman
author_rank: Regular Contributor
timestamp: January 04, 2012, 07:08:37 am
content: Berillium copper is flexible and does not spark easy, but is a very good electrical conductor.So, they use copper in alloys, to some extent.

author: samgab
author_rank: Frequent Contributor
timestamp: January 08, 2012, 12:08:22 am
content: I think you got an amazing bargain there! Have you the means to check it's accuracy?

author: Fraser
author_rank: Super Contributor
timestamp: January 08, 2012, 11:18:41 am
content: When considering who would have an interest in an EX model, it may become clear why no one bid against youThe EX 87V is a specialist product serving the explosive atmosphere market where lives are at risk. The standard 87V meets the needs of everyday users and may be sourced cheaper than an EX model. A person who's life is on the line when using an EX model is unlikely to wish to take the risk that the unit no longer meets the EX specification or has been tampered with. Its too late when there is a loud bang !It's a bit like buying a used defibrillator... you can't test it on yourself as that's crazy dangerous....so will it work when it is actually needed or is it faulty/damaged ? Those who work in high risk environments need to have total trust in the equipment they are using..... second hand kit with unknown provenance would be considered foolish to such people.... I have worked in such environments so know first hand. Life insurance also becomes an issue....if you use dodgy kit and die, the insurer may not pay out for your family.Retesting an unknown provenance used EX meter can also be very expensive, with the risk of test fail resulting in scrapping of the kit.You have a very nice meter that will never suffer from moisture ingressEnjoy it....but don't expect to sell it on to someone working in explosive atmospheres

author: Fraser
author_rank: Super Contributor
timestamp: January 08, 2012, 02:27:00 pm
content: Another ATEX rated 87V recently sold for GBP200 so that seems to be the UK market price at the moment.http://www.ebay.co.uk/itm/Fluke-87v-Atex-Rated-Multimeter-Ex-/280801489555?pt=UK_Consumer_Professional_RL&hash=item416112b293I have seen used standard 87V units sell for between ~GBP100 and GBP250 so there seems a huge range in the market value of these things. You certainly have a gold standard unit though so the price was very good indeed.

author: xavier60
author_rank: Super Contributor
timestamp: January 29, 2020, 08:34:34 am
content: I bought a used 87V Ex on ebay. I soon noticed that the red holster is much softer and chafes more easily than the yellow ones of my 87V's.Is this a known problem?