Author Topic: Fluke 731B Battery Replacement  (Read 626 times)

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Offline VK5RC

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Fluke 731B Battery Replacement
« on: December 09, 2016, 04:40:02 pm »
An eBay purchase of an old Fluke 731B soon showed that although it worked reasonably well (quick fire up only) and was able to charge its internal NiCad batteries, they did not hold charge for more than an hour or so. Opening it up revealed a bit of 'battery cancer' which had also wicked down the cable to the main board. An EEV blog postee ( I can't find the post now!) had had good results with routine rechargeable batteries. I had a few (well quite a few) eneloops (700mAHr) lying around. I like the retention of charge feature of eneloops.
I used the technique in the Mr Carlson's Lab Youtube (making a new battery for a Tek 200 series mini-scope) to solder the batteries together. sandpaper, flux, solder quickly and have an IPA soaked rag handy to cool off rapidly after.
New connectors and a good clean of the PCB.
A quick current measurement showed a charging current of 18mA (~0.025C) on mains and a battery draw of 8mA when switched on but not connected to the mains.
Hopefully they will last a while.
« Last Edit: December 09, 2016, 05:18:06 pm by VK5RC »
Whoah! Watch where that landed we might need it later.
 
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Online lowimpedance

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Re: Fluke 531B Battery Replacement
« Reply #1 on: December 09, 2016, 05:11:44 pm »
Would that be a 731B instead of 531b ?.
You call that current ?.......
I'll show you current !
 the odd multimeter or 2 or 3 or 4...or........never mind
 
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Offline VK5RC

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Re: Fluke 531B Battery Replacement
« Reply #2 on: December 09, 2016, 05:17:39 pm »
D'oh , Thanks.  731B 731B NOT 531B,
EDIT Title altered
« Last Edit: December 09, 2016, 05:19:17 pm by VK5RC »
Whoah! Watch where that landed we might need it later.
 


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