Fluke 87 completely dead. Was working the other day ! - Page 1
Forum section: electronics / testgear

author: snoopy
author_rank: Frequent Contributor
timestamp: July 04, 2017, 01:23:48 pm
content: Yep switched it on today and it is as dead as a tack !Was working perfectly the other day. Perhaps the cold weather here in Melbourne has had an effect.Battery is OK. Any tips for checking it ?cheersdavid

author: MosherIV
author_rank: Super Contributor
timestamp: July 04, 2017, 01:43:25 pm
content: HiTry looking here :http://mrmodemhead.com/blog/tag/80series/Try cleaning the rotary switch contacts and the pattern on the board.Make sure the contacts springs are pushing down on the board.Good luck

author: joeqsmith
author_rank: Super Contributor
timestamp: July 04, 2017, 03:39:19 pm
content: Rather than risk further damage, why wouldn't you just return it with their life time warranty?

author: retiredcaps
author_rank: Super Contributor
timestamp: July 04, 2017, 05:40:55 pm
content: Quote from: snoopy on July 04, 2017, 01:23:48 pmSorry if this seems like a basic question, but what is OK? How did you test the battery?The reason for asking is someone posted something similar saying the battery was okay and it ended up being the battery was not okay. A fresh 9V battery fixed his problem.

author: retiredcaps
author_rank: Super Contributor
timestamp: July 04, 2017, 05:43:58 pm
content: Quote from: snoopy on July 04, 2017, 01:23:48 pmIf you hookup the Fluke 87 to a variable DC power supply set to 9V, how much current does the 87 draw?

author: robert_
author_rank: Regular Contributor
timestamp: July 04, 2017, 06:11:33 pm
content: Check the battery voltage at the board, quite often the wires break off inside the battery connector.

author: alm
author_rank: Super Contributor
timestamp: July 04, 2017, 06:43:41 pm
content: Quote from: retiredcaps on July 04, 2017, 05:43:58 pmAnd do not make the mistake I made a long time ago in an absent-minded moment: the polarity of the connector is reversed relative to that of the battery, i.e. the wider terminal is the positive terminal. That mistake (with a cheap DMM) only killed a CMOS hex inverter, fortunately.

author: snoopy
author_rank: Frequent Contributor
timestamp: July 05, 2017, 08:48:54 am
content: Thanks for all of the replies. Looks like it was the LCD rubber connector playing up again. This time I cleaned it with isopropyl alcohol rather than contact cleaner and now its better than everBut may need a better fix in the future if it plays up again. Saw one dude on youtube using a thin layer of conductive grease.As for a lifetime warranty I certainly don't have the original receipt nor am I the original owner of this meter.cheersdavid

author: Fungus
author_rank: Super Contributor
timestamp: July 05, 2017, 12:05:32 pm
content: Quote from: snoopy on July 05, 2017, 08:48:54 amIt doesn't matter.

author: snoopy
author_rank: Frequent Contributor
timestamp: July 05, 2017, 12:38:37 pm
content: Quote from: Fungus on July 05, 2017, 12:05:32 pmWho are the agents for Fluke in Australia ? Has anyone taken advantage of the life time warranty ?

author: Muttley Snickers
author_rank: Unknown
timestamp: July 05, 2017, 01:23:33 pm
content: Quote from: snoopy on July 05, 2017, 08:48:54 amYep, I've been down that same path before and you cannot claim warranty down here without proof of purchase from a local authorised distributor or agent, purchases from online auction sites or overseas imports are not recognised and they will not honour the warranty.Quote from: Fungus on July 05, 2017, 12:05:32 pmIt does matter down here, read the local Fluke AU site for confirmation.http://www.fluke.com/fluke/auen/support/warranties/defaultQuote from: snoopy on July 05, 2017, 12:38:37 pmCelemetrix Australia Pty Ltd are the service agents and from my experience they are very good to deal with.http://www.celemetrix.com.auhttp://www.fluke.com/fluke/auen/support/service-technical-support/default

author: Nusa
author_rank: Super Contributor
timestamp: July 05, 2017, 02:28:40 pm
content: Never looked before, but apprently "lifetime" is the manufacturing lifetime of the product + 7 years and only for the original purchaser, even in the US market:http://en-us.fluke.com/support/warranties/QuoteAnd now you also know why the Chinesium Fluke models are so cheap...no warranty!

author: retiredcaps
author_rank: Super Contributor
timestamp: July 05, 2017, 05:28:31 pm
content: Quote from: snoopy on July 05, 2017, 08:48:54 amSeehttp://mrmodemhead.com/blog/fluke-8x-faded-lcd/

author: Fungus
author_rank: Super Contributor
timestamp: July 05, 2017, 07:18:06 pm
content: It's weird that the entire display would go all at once. Normally it starts with single LCD segments.

author: snoopy
author_rank: Frequent Contributor
timestamp: July 06, 2017, 05:28:35 am
content: This dude does the LCD repair but pulls the rubbers off the LCD and cleans the rubbers and LCD glass contacts. Not seen this done before

author: snoopy
author_rank: Frequent Contributor
timestamp: July 06, 2017, 05:31:29 am
content: Quote from: Fungus on July 05, 2017, 07:18:06 pmOne of the wires had come off the battery but only after I had removed the board from the case. I was measuring voltage at the board prior and it was ok. Somehow when I removed the board it came back to life again so not sure exactly if it was the LCD but assumed so because when I pushed it is when it sprang to life again.cheers

author: snoopy
author_rank: Frequent Contributor
timestamp: July 07, 2017, 12:52:44 am
content: Just a heads up. Removing the rubbers from the LCD glass and cleaning both the rubbers and the glass contacts with isop has made a big difference. Also using an eraser on the pcb contacts also helpedThere are no longer any faded segments and hopefully this has fixed the NO switching on problem

author: snoopy
author_rank: Frequent Contributor
timestamp: August 24, 2017, 06:01:11 am
content: Quote from: Fungus on July 05, 2017, 07:18:06 pmYou are right ! I spoke too soon.Turned it on the other day and it was completely dead again but this time I could not get it to workThe display issue was just a red herring and cleaning the switch contacts did nothing. Thought about ditching it but these are still a good meter and it came from my late father and I had just restored the LCD issue so its worth fixing. I'm printing out the manual and will investigate further !regards

author: snoopy
author_rank: Frequent Contributor
timestamp: August 27, 2017, 01:49:05 am
content: Actually I fixed this unit last nightThe supply trace from the positive battery terminal was open circuit on the board right at the point at where the end of the W2 jumper (green colored jumper) is soldered to the board and fans off to other parts of the circuit. It looked like the thin trace was corroded or had been burnt open perhaps by someone reversing the battery terminals at some stage and the reverse diode protection had resulted in excessive current vapourising or weakening the track. I managed to trace the track and find a via further down the track where I could solder a bit of wire wrap wire back to the end of the W2 jumper. The tracks on the board are so narrow probably of the order of 4-5 thou thick it's not surprising that something like this could happen !

author: retiredcaps
author_rank: Super Contributor
timestamp: August 27, 2017, 02:00:59 am
content: Quote from: snoopy on August 27, 2017, 01:49:05 amGlad you got it fixed and shared the fix.

author: snoopy
author_rank: Frequent Contributor
timestamp: August 27, 2017, 02:13:51 am
content: Quote from: retiredcaps on August 27, 2017, 02:00:59 amA weakness in the design is the reverse protection diode (CR4-1N4007) located all of the way at the end of very thin pcb traces. Anyone with poor eyesight fumbling around with the battery and inadvertently reversing the connection could have easily cooked or weakened the traces at some point !A possible mod is to put a reverse protection diode right at the battery entry point on the board.

author: alm
author_rank: Super Contributor
timestamp: August 27, 2017, 07:35:57 am
content: Maybe the traces were designed as deliberate fuses to protect the down stream circuit?

author: snoopy
author_rank: Frequent Contributor
timestamp: August 27, 2017, 07:40:04 am
content: Quote from: alm on August 27, 2017, 07:35:57 amThe reverse protection diode is right at the end of that line so if the trace is burnt out near the diode all of the other circuity before it will be exposed to reverse polarity. This is not a well thought out layout