fluke 77 fix or replace

[yero]

I applied 100+ volts AC while the meter was in ohms mode. now when in ohms mode the display gives multiple readings with the test leads shorted. ac volts has gross inaccuracys. Should they be able to handle this mis application? In my case it did not!!! What fluke model currently available is equivalent to the 77 or is the meter worth reparing. Is the fluke 115 as good as the 77 or better

[davada]

Originally Posted by yero

I applied 100+ volts AC while the meter was in ohms mode. now when in ohms mode the display gives multiple readings with the test leads shorted. ac volts has gross inaccuracys. Should they be able to handle this mis application? In my case it did not!!! What fluke model currently available is equivalent to the 77 or is the meter worth reparing. Is the fluke 115 as good as the 77 or better

I would say fix the 77. I have one. it's an excellent meter.


David.

[yero]

Disassembled the fluke 77 meter. The battery,leads and fuse was good. Spoke to Fluke. Teck assistance checked the serial number indicating the meter was made in the early 1980's.I was told that many Fluke custom made IC's are no longer made. I was checking around with another meter and checked for continunity of what looked like 3 watt resistors with two bands. One of the resistor looking component read zero ohms, the other similar looking resistor with a green band on one end and a blue band at the other end read open circuit. The one end was connected to the ohms volt diode terminal. The meter could not be open circuited at the input. must be some kind of fusable link. Jumpered the two terminal device and the meter works. Replaced the component with a 3/4 inch wire the same thickness of the replaced lead. Will have to be more carful in the future!

Jason: I have read your mission statement or purpose for this forum and it is a nobel one, to learn and to help others. Have you noticed that the second part seems to be a bit lacking? 1 responce out of 168 views. I would be interested to to know how many were members? I am learning so much because of your efforts, at the same time I struggle with fundmentals. It seem that fundmental type questions responces are harder to come by at times. Oh yes I need to do a little more googling first mister one member responded- about SIT circuit diagrams. what can you do, It is what it is! cheers, Yero

[yero]

Couldn't edit after 30 minutes. So again it is what is, Yes? Your comments are welcome and appreciated

[AJT]

yero, have faith and keep on looking/asking......we are fortunate to be living in a era where information is easily obtained....i am surprised at how many hits i get when i type my name in google....

i have a sneaky feeling that fluke wants you to buy a new meter.....i have 3 Fluke an i hope i can use them for a long time....

[sofaspud]

+1
Keep on keepin' on, yero. I admit knowing diddly about SIT amps. And you did good with your meter! Give yourself a pat on the back. Great job.
BTW, last I knew, Fluke had a flat-rate repair fee for their handheld DMMs. You might post a pic of that component, or solicit another forum member to check inside his meter, to get a better idea of what got replaced. You may be better off inserting a fuse at that location to maintain the circuit protection.

[davada]

Originally Posted by yero

Disassembled the fluke 77 meter. The battery,leads and fuse was good. Spoke to Fluke. Teck assistance checked the serial number indicating the meter was made in the early 1980's.I was told that many Fluke custom made IC's are no longer made. I was checking around with another meter and checked for continunity of what looked like 3 watt resistors with two bands. One of the resistor looking component read zero ohms, the other similar looking resistor with a green band on one end and a blue band at the other end read open circuit. The one end was connected to the ohms volt diode terminal. The meter could not be open circuited at the input. must be some kind of fusable link. Jumpered the two terminal device and the meter works. Replaced the component with a 3/4 inch wire the same thickness of the replaced lead. Will have to be more carful in the future!

Jason: I have read your mission statement or purpose for this forum and it is a nobel one, to learn and to help others. Have you noticed that the second part seems to be a bit lacking? 1 responce out of 168 views. I would be interested to to know how many were members? I am learning so much because of your efforts, at the same time I struggle with fundmentals. It seem that fundmental type questions responces are harder to come by at times. Oh yes I need to do a little more googling first mister one member responded- about SIT circuit diagrams. what can you do, It is what it is! cheers, Yero

Hi Yero,

Fluke uses precision shunts in their meter. It would be worth grinding the guys at fluke to find out exactly what that part is. If you know the details about it there are parts available that can do the job properly so the meter retain it acccurracy and precision.

Cheers,

David.

[ronaldw441]

Manuals Search

Download the 70 Series service manual then you'll know what you're dealing with.

[imix500]

Definetely replace the fusible resistor. As you found out its crucial for protection of the front end.
I would be very suprised if Fluke didn't have one available as a replacement part. While you're ordering consider picking up a spare set of fuses if you plan on holding on to it for a bit.

[mrmodemhead]

I have replaced that 1K fusible resistor with this Vishay part before. The tolerance is 5% instead of the original 2%, but I don't think that the value of this resistor is crucial to the calibration of the meter. I am referring to 77 and 77-II models. Not sure about the series III and IV models.