Re: Polarity reversal protection,how to??

From: Joop (l_o_u_s_take_most_away_at_xs4all.nl)
Date: 11/13/04 

Date: Sat, 13 Nov 2004 12:06:04 +0100

Fred Bloggs <nospam@nospam.com> wrote:

>
>
>Antonio Spedicato wrote:
>> Hy, i would to build a polarity protection for my dive light (12 volts
>> nimh batteries) but i don't known ho to do it!!
>> Can someone help me?
>> There are 10 batteries 1,2 volts 3000 mah serial installed.
>> Thanks
>> Antonio-Italy
>
>I think we have posted this 10,000 times in the past:
>
> View in a fixed-width font such as Courier.
>
>
>
> +--------------+---------+
> | | |
> | | |
> | | +-+
> --- | |L|
> - BATT | |O|
> | | |A|
> | | |D|
> | | +-+
> | G |
> | ----- |
> | - - - |
> +------------D S-------+
>
> N-CH MOSFET

When one wants to connect multiple devices to the same battery and
share a common and quality ground (HF equipment) it would be desirable
to 'switch' in the + line.
Do you perhaps have a simple solution for this as well? I was thinking
along the lines of moving this mosfet to the + line and use an helper
voltage generated by some inverters to lift the gate way above the
battery level.
But when things get too complex, a relay would become a simpler, but
less energy effecient solution.

Joop

Relevant Pages

  • Re: Polarity reversal protection,how to??
    ... Joop wrote: ... > battery level. ... > less energy effecient solution. ... Just use a P-channel FET with SOURCE terminal on the LOAD, GATE to gnd, ...
    (sci.electronics.design)
  • Re: HELP With Step-Down Transformer and Converter
    ... 12 Volt Cylindrical Battery, looks like a big AAA Batery ... Where do I put the Switch, Shunt and Millivoltmeter in the diagram ... circuit ON/OFF at precise time. ... Just turn off the 240 volts to the primary of the transformer when you're ...
    (sci.electronics.design)
  • Re: 12v TV
    ... what was being pointed out is that the mains power supply outpts 12 volts... ... hence the TV's components are made using the lowest tollerance parts available, no need to use more expensive higher voltage parts when the TV will never see more than 12.3 volts. ... as a fair few people found out tho, plugging it into the caravans battery directly... ... i have a large solar array on my vans roof, and it does an equalizing charge every month, takes the batteries upto 16 volts for a few hours to balance them all out and stir up the cells, my Tv would have let the magic smoke out first time it did that for sure. ...
    (uk.rec.caravanning)
  • Re: 12 volt power source?
    ... and Greg Procter instead replied: ... 12 volt battery which is never, ever going to be at 13.8 volts. ... The battery is in circuit between the generator/alternator and the load, ... it's an integral part of the voltage regulation circuit. ...
    (rec.models.railroad)
  • Re: Fixing Briggs and Stratton lawn tractor Update 2
    ... Tested the battery under load one time. ... Got 10.5 volts. ... On the negative side I got a reading of .25 volts. ... Still got a low voltage reading at the starter motor. ...
    (alt.home.repair)
Quantcast