1. Fluke 8502A (steve gunsel)
2. Re: Fluke 8502A (Rob Klein)

Rob, I have removed the 3 optional plug-in boards and that does not help. There are 6 plug-ins that must be plugged in. I checked the power supply voltages and they are all in spec. When powered up, it ... Recognizes the software (3.0.0, newer than that in the manual); Recognizes the optional plug-ins, when plugged in; Displays 112.94 VDC with the inputs shorted, but this changes with different ranges. AC volts behave similarly. Steve At 08:00 AM 5/7/2010, you wrote: >Send volt-nuts mailing list submissions to > volt-nuts@febo.com > >To subscribe or unsubscribe via the World Wide Web, visit > https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts >or, via email, send a message with subject or body 'help' to > volt-nuts-request@febo.com > >You can reach the person managing the list at > volt-nuts-owner@febo.com > >When replying, please edit your Subject line so it is more specific >than "Re: Contents of volt-nuts digest..." > > >Today's Topics: > > 1. Fluke 8502A (steve gunsel) > 2. Re: Fluke 8502A (Rob Klein) > > >---------------------------------------------------------------------- > >Message: 1 >Date: Thu, 06 May 2010 08:04:41 -0400 >From: steve gunsel <sgunsel@verizon.net> >Subject: [volt-nuts] Fluke 8502A >To: volt-nuts@febo.com >Message-ID: <0L1Z00HS8YX7MQ31@vms173001.mailsrvcs.net> >Content-Type: text/plain; charset=us-ascii; format=flowed > >Hi, > >Does anyone have experience repairing one of these? I have two and >neither works. The first one lights up, but with random digits on the >display. I picked up the second hoping to get some spare parts, but >almost all of the boards are marked "BAD", which they appear to >be. I downloaded the service manual, but at step 3 (of 103) it says >to "insert interconnect-monitor PCB in the isolator slot", which I do >not have. Is this thing fixable or should I toss it? >Thank you. > >Steve - N8MYA >Medina OH > > > > >------------------------------ > >Message: 2 >Date: Thu, 06 May 2010 19:20:26 +0200 >From: Rob Klein <rob.klein@smalldesign.nl> >Subject: Re: [volt-nuts] Fluke 8502A >To: Discussion of precise voltage measurement <volt-nuts@febo.com> >Message-ID: <4BE2FA5A.7060404@smalldesign.nl> >Content-Type: text/plain; charset=ISO-8859-1; format=flowed > >Hi Steve, > >I would just unplug all module except the controller. See if the display >is normal, then plug the modules back in, one at a time (power-off/on in >between, of course!). When >the display goes bad again, there's your culprit. Of course, if the >display is bad with just the controller, well ... good luck ;-). > >I have an 8505A myself, with a bad IEEE interface, which also causes the >display to go mad. Haven't had the time to repair it yet, but no >interface is not such a big deal. > > >Regards, >Rob. > > >steve gunsel schreef: > > Hi, > > > > Does anyone have experience repairing one of these? I have two and > > neither works. The first one lights up, but with random digits on the > > display. I picked up the second hoping to get some spare parts, but > > almost all of the boards are marked "BAD", which they appear to be. I > > downloaded the service manual, but at step 3 (of 103) it says to > > "insert interconnect-monitor PCB in the isolator slot", which I do not > > have. Is this thing fixable or should I toss it? > > Thank you. > > > > Steve - N8MYA > > Medina OH > > > >------------------------------ > >_______________________________________________ >volt-nuts mailing list >volt-nuts@febo.com >https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts > >End of volt-nuts Digest, Vol 9, Issue 5 >*************************************** > >No virus found in this incoming message. >Checked by AVG - www.avg.com >Version: 8.5.437 / Virus Database: 271.1.1/2859 - Release Date: >05/07/10 06:26:00

Steve, Well, that's quite something different than what I understood from your first post, where you were talking about "step 3" in the manual. But clearly, since you now say it recognises the firmware version and modules, then proceeds to display some -erroneous- value, something else is going on. You should go through the procedure and take a turn at step 4, rather than 3. This leads you to step 59 (or at least it does in my version of the manual (rev 1 7/81). Since you've already established that the supply voltages are in spec and since you do not have the mythical Interconnect-Monitor PCB, I would follow the steps from 70 onwards, to check all the analogue modules. If those are OK, you most probably have a defective isolator. Good luck! Rob. steve gunsel schreef: > Rob, > > I have removed the 3 optional plug-in boards and that does not help. > There are 6 plug-ins that must be plugged in. > I checked the power supply voltages and they are all in spec. > When powered up, it ... > Recognizes the software (3.0.0, newer than that in the manual); > Recognizes the optional plug-ins, when plugged in; > Displays 112.94 VDC with the inputs shorted, but this changes with > different ranges. > AC volts behave similarly. > > Steve