Protection Diodes On the Dick Smith Meter

Actually I am now adding a MOV to all my Bob Parker (DS) ESR kits. I then tested the shop ESR kit to 350VDC @20MA with no ill effects. Not that I recommend you try this - after all I have a lot of spare parts if something goes wrong...still, it is nice to still let the kit test batteries ESR (you can check gel-cell batteries to see how they are).

I sell the MOV for $5US including postage to Canada/USA, or you can get one from Digi-Key or somewhere. I used a 28V 500A unit...

John :-#)#

I went ahead and ordered NTE1V014, as the panasonics aren't sold by mouser. Here is the spec sheet for it:

Would there be any benefit in placing more than one across the leads (in parallel)?

If I'm not mistaken this

- Mike

Oh, nevermind I see you ordered a MOV.. Good Move..

- Mike

I just got a cross reference request from mouser to the Panasonics I made last week and they suggested:

Pretty much the same thing, but .23 each, the NTE were about $1.25 each.

snipped-for-privacy@hotmail.com hath wroth:

Which voltage MOV did you select? My guess(tm) is that the lowest possible voltage should work.

That would allow the protection MOV to handle more overload power for a longer time. At some point, methinks a series fuse before the MOV might be a good idea.

I recommend using a 22V MOV so you can still easily test car batteries for internal ESR. That is one of the abilities of the DS ESR kit! I also tested my kit to 350V @20ma.

John :-#)#