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Electronics => Projects, Designs, and Technical Stuff => Topic started by: Electro Fan on October 15, 2021, 11:41:25 pm

Title: Battery for Standard Pneumatic 620 Wire Wrap Gun
Post by: Electro Fan on October 15, 2021, 11:41:25 pm

Anyone have an idea how to determine what a suitable replacement NiCad rechargeable battery might be for a Standard Pneumatic 620 wire wrap gun based on the info in this spec sheet?

http://www.ralphselectronics.com/ProductImages/STPM-62094.PDF (http://www.ralphselectronics.com/ProductImages/STPM-62094.PDF)

Also, if I have a battery that I think might be a genuine original that still runs the wire wrap gun what would be the best way to test/measure the battery in an attempt to identify a suitable replacement?

The original 120V charger is marked 2.9VDC and and 200mA, but when I measure the charger with a DMM at the DC jack I get about 1.9V. The potentially original battery measures 2.9VDC when it's charged up.  The battery diameter measures about 26mm and the length (which might be two batteries joined together) is about 96mm or 99mm (maybe 100?mm) including the positive terminal.

Thanks

Title: Re: Battery for Standard Pneumatic 620 Wire Wrap Gun
Post by: NiHaoMike on October 16, 2021, 01:32:28 am

Just use two NiMH AA in AA to C adapters. Use an external charger to charge them.

Title: Re: Battery for Standard Pneumatic 620 Wire Wrap Gun
Post by: Electro Fan on October 16, 2021, 03:19:04 am

Thx NiHaoMike, Other than price any reason to not just use 2 C batteries?

Title: Re: Battery for Standard Pneumatic 620 Wire Wrap Gun
Post by: NiHaoMike on October 16, 2021, 03:24:13 am

That works as well, but NiMH C tends to be more expensive than NiMH AA. Might as well just get a second set of AAs so you can switch between them.

You can also 3D print an adapter to use a single 18650, using one of those USB charger/protection boards and possibly a series diode to drop the voltage a bit.