Latest Discussions : Tools & Workshop

crotsc

08:51AM | 11/18/09
Member Since: 11/16/09
2 lifetime posts
I bought a craftsman cordless drill 16.8V a while back and the charger has gone bad recently. When the battery is plugged in, the LED is lit up for few seconds and turned off. Battery doesn't get charged. I opened up the circuit board, measured on the components and they seemed to be fine (i.e. R2(1/4w)=216ohm, R3(2W)=15ohm, D1(Vfw)=0.55V, NTC=2ohm). Someone in another forum discussion suggested to short out the thermistor for the battery to get charged. Is it true? If so, what is the thermistor there for? I drew out the schematic but couldn't analyze how it works. Another word, how does the charger work? I really appreciate if someone can shed some light on it. Thanks.

chgodoc

12:07PM | 12/31/09
Member Since: 11/27/09
1 lifetime posts
There are previous entries here with more details. see http://www.bobvila.com/wwwboard/messages/312747.html

Part is Manufacturer: BOURNS

Newark Part Number: 61J7391

Manufacturer Part No: MF-R030-0-99

I just ordered the thermistor from Newark Electronics, cost 30 cents + $5 shipping. It's the exact brand used by Sears/Ryobi. Mouser.com has a similar one, but not the same brand.

Ordering info found here(copy & paste in browser without line breaks)

http://www.newark.com/jsp/search/productdetail.jsp?SKU=61J7391

Haven't installed it yet, but should be relatively easy to solder it in. Don't use too much heat, though.

Hope this helps.

ChgoDoc
2758 heres where to get r


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