Lost polarity of battery charger

Thanks guys, I will double check my DVM for polarity information other wise a potato will get the knife.
Have a good day
Ray
 
I cannot recommend this but I am told it works. Proceed at your own risk. Touch both leads to your tongue at the same time. The negative terminal will hurt more. The difference is noticeable.
Robert
 
rwm said:
I cannot recommend this but I am told it works. Proceed at your own risk. Touch both leads to your tongue at the same time. The negative terminal will hurt more. The difference is noticeable.
Robert
Click to expand...

Never noticed that with 9V batteries...and you think it really hurts more for electrons to go into your tongue vs out of your tongue (and it's the same "amount" of electrons)?
 
rwm said:
I cannot recommend this but I am told it works. Proceed at your own risk. Touch both leads to your tongue at the same time. The negative terminal will hurt more. The difference is noticeable.
Robert
Click to expand...
Will your tongue turn green at the negative side too?
 
Hook to a 12v light bulb. If it lights you have it right. If backwards the room will get dark due to sucking the light back in.

Seriously, someone around you must have a volt meter you could borrow for a few minutes. I don't know if I would trust any of the potato methods when I hook to a 12v battery full of acid waiting to burn you if wrong. A LED car or trailer light would also work.
 
I can't imagine not owning a digital multimeter. You don't need to buy a $400 Fluke. Harbor Freight literally gives away the cheap little $6 red ones. The "expensive" 11 function $24 ones at Harbor Freight aren't half bad (that's what I keep on my boat). On Ebay you can buy meters shipped to your door for less than $10. These cheap meters may not be the the highest quality and may not be appropriate for every use but they will work fine for 99% of the things you are likely to do around the home workshop.
 
jim18655 said:
Hook to a 12v light bulb. If it lights you have it right. If backwards the room will get dark due to sucking the light back in.
Click to expand...
This is a valid method yet difficult to see for obvious reasons.
Small pets available cheaply at pet stores also display an uncanny ability to sense polarity, gerbils will always move toward the conductor of less potential. Guinea pigs the opposite yet are excellent in a chicken broth afterwards. I hope this helps.
 
Ge my charger will tell you if you hook it up backwards.
 
The results of checking my DVM showed a real thick minus sign that without my glasses I thought was fine print, the meter does have colored connections for the wire leads so the polarity was found and the clamps installed. My father sold power plants in the late 1920s many of them direct current and that's where I learned about the potato polarity check. With out the small colored ring on the DVM it would have been down to the potato test. You will be glad to know no potato was injured except for those in the hash browns yesterday morning.
Have a good day'
Ray
 
You must log in or register to reply here.
Back
Top