Fluke 77 - I think I killed her!

[Ign]

I was trying to test my bug zapper (incidentally, don't do this! I now know....)

The grid arc'd across the leads and now she fires up w dim, muddled screen. I was in 120VAC, fused. The fuse is fine and the battery tests at 9.07V

I'm no EE, in case you haven't figured that out yet - - anything else I should try?

 

[Brownsfan]

I think it was just coincidence that happened while testing. The fluke meters of that vintage are known for that screen problem. The repair kits are all over eBay. I had a 73 that did the same thing.

 

[Davefr]

I agree with Brownsfan.

You don't need an LCD repair kit. Just take a q tip and wipe the rubber connectors and LCD contacts with IPA.

Lot's of youtube videos show how to do it.

The "achilles heel" of Fluke meters is their crappy LCD interconnects.

 

[royesses]

You can try a repair to the zebra strip. Remove the display and find the zebra strips. Clean the gold plated pads with 91% alcohol and a qtip. If the contacts are really dirty wipe them with a clean piece of copy paper. Reassemble and test. Many times when high voltage is concerned the inputs and outputs of the driver chip gets fried.

http://shop.flukerepairkit.com/Fluke-70-Series_c4.htm


Good luck.

 

[Ign]

I had no idea the displays were flakey, I'll look into it.

 

[FigureItOut]

I've heard of that issue with them too, yours is not a....fluke.

Sent from my SAMSUNG-SGH-I337Z using Tapatalk

 

[whitetailhntr]

I would never mess with the internals if a multi-meter for safety reasons. If its faulty replace it.

 

[TK-421]

I would never mess with the internals if a multi-meter for safety reasons. If its faulty replace it.

As long as you're not being stupid I really don't understand why you wouldn't try and repair it. Not like you're ripping things apart and putting it back together all willy nilly, or soldering on new wires to bridge two different sections that weren't bridged before. A simple cleaning won't hurt anything, and if it does then you have other, bigger problems.

 

[TigerDude]

always test a multimeter against a known source before using it to check voltage.

Sounds to me like it got hit with the super high volts of the screen

 

[R.Anderson]

I would never mess with the internals if a multi-meter for safety reasons. If its faulty replace it.

So if you blow a internal fuse you would just throw the meter away???

As long as you're not being stupid I really don't understand why you wouldn't try and repair it. Not like you're ripping things apart and putting it back together all willy nilly, or soldering on new wires to bridge two different sections that weren't bridged before. A simple cleaning won't hurt anything, and if it does then you have other, bigger problems.

I agree, no harm in playing with the the zebra strip or cleaning contacts. Just test the meter on known sources when done.

I was trying to test my bug zapper (incidentally, don't do this! I now know....)

The grid arc'd across the leads and now she fires up w dim, muddled screen. I was in 120VAC, fused. The fuse is fine and the battery tests at 9.07V

I'm no EE, in case you haven't figured that out yet - - anything else I should try?

Bug zappers are well over 1KV(1000Volts), transformers I have from older zappers are 7KV(7000Volts). For giggles I killed several of those HF freebie meters with em.

 

[californiajim]

That sounds like what I did to my Sperry DM5300 only I tried to check my electric fence.. Now all I get on the screen is O.L...

 

[R. Johnson]

The flukes have a 1k ohm fusible resistor used to protect the input. Check that if you have problems after fixing the display problem (90% chance just cleaning the zebra strip contacts will fix that).

Sent from my SM-G930V using Tapatalk

 

[Cope]

I cleaned the display on my Fluke 83 several times and finally broke down and bought a replacement off eBay. Never had a problem again, but I discovered I could have bought the screen straight from Fluke cheaper.

 

[redmondjp]

I cleaned the display on my Fluke 83 several times and finally broke down and bought a replacement off eBay. Never had a problem again, but I discovered I could have bought the screen straight from Fluke cheaper.

And they also sell LED backlight upgrade kits too, which consume less power than the OEM incandescent ones (at least, for the older meters that I have). It's very easy to do this at the same time as replacing the zebra strip.

 

[6PTsocket]

I would never mess with the internals if a multi-meter for safety reasons. If its faulty replace it.

Many people that own good multi meters are experienced enough to work on them. There is nothing inherently dangerous here. The case and leads still protect you from shock, whether the meter is working or not. By all means, do not work beyond your comfort zone.

 

[6PTsocket]

If you want to play with high voltage, Fluke has a number of high voltage probes. I think they divide by 100. There are nice big arc shields and long handles to protect you from getting zapped, I see them on eBay all the time and are available with a few different maximum ratings. Virtually all DMMs have a 10 meg ohm input impedance so these probes will work with almost all of them, regardless of brand. There are other brands of probes too. You do not have to match brands.

 

[Citation]

I was trying to test my bug zapper (incidentally, don't do this! I now know....)

The grid arc'd across the leads and now she fires up w dim, muddled screen. I was in 120VAC, fused. The fuse is fine and the battery tests at 9.07V

I'm no EE, in case you haven't figured that out yet - - anything else I should try?

It might be repairable but you will need some electrical skills to figure it out. The fuse protects in the case of over current. You weren't in current mode so it doesn't help. There are several parts used to protect the meter from an over voltage event but often they are like airbags, you use them one then replace them.

Check out a blog by Mr Modemhead (do a web search). It will be a starting point to understand what you are up against. After that buy a used Fluke 27 on eBay and call it good.

 

[Ign]

Thank you all for the input!

I STILL haven't "had time" to do anything w this, but apparently I have time to peruse GJ and the local pawn.

I found a Fluke 179 at the local pawn, they took $60 for it. So far I've just confirmed DC voltage readings against a known good Innova meter on a 3V battery and my truck battery, but it appears fine (shrug). It's got some cosmetic damage on the yellow surround, it's pretty dirty, and the rear arm to prop it up is broken.

The biggest problem? I'm severely out-classed w this meter, as indicated by the mere fact I had to start this thread. But they appear to sell for $300+ new so it seemed like a solid deal

 

[DHCrocks]

And they also sell LED backlight upgrade kits too, which consume less power than the OEM incandescent ones (at least, for the older meters that I have). It's very easy to do this at the same time as replacing the zebra strip.

tell me more....i have a 83 that doesn't have a back light can it be retrofit?

 

[redmondjp]

tell me more....i have a 83 that doesn't have a back light can it be retrofit?

If you have one of the early 83s, I'm not sure that you can. This Ebay guide gives more details on the 80-series meters - you may be able to ask that question to the owner of that site:

http://www.ebay.com/gds/Fluke-Meters-80-Type-Models-and-Series-/10000000007491382/g.html

 

[bsaint]

A bug zapper is literally at least a thousand volts. The fuse is only for current draw. You basically esd killed it.

 

[pedrodagr8]

A bug zapper is literally at least a thousand volts. The fuse is only for current draw. You basically esd killed it.

Most bug zappers are 2-5kV actually with some even more. They are REALLY good at killing multimeters. The older the meter, the less likely it is to handle it. They were not designed with ESD in mind, more modern meters are designed to handle that (except for Uni-T).