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Changing The Polarity Of Your Car

 

If your car battery is connected as Positive Earth, this is what you will need to do to change it to be Negative Earth.

First you need to disconnect any radio that you may have as this is going to be the wrong polarity as is any electrical clock. Remove the coil connections (you might need a new one but not often) If you have an Amp meter this will need changing over later so remember this. Now disconnect your battery and your dynamo but not the regulator. You need to ensure that both the D and the F terminals are not connected to any cables.

1.   With the ignition off, change the battery connections over; (- will now be the Earth Cable instead of +) you will need to change the terminals on the cables, as they are different sizes too.

2.    With a spare length of cable run a wire from the + (positive) terminal (now non earth) to the dynamo, but don’t connect it yet.

3.   Ensure you have removed all polarity sensitive equipment from the vehicles electrics.

4.   Take the end of the wire from the battery and "FLASH" the end onto the F terminal of the dynamo, do this a couple of times and you will see a bright spark, this is normal. You have now changed the polarity of the dynamo.

5.   Disconnect the earth of the battery reconnect the D and F terminals to their respective connectors and check they are still on the regulator. Check the wiring of the coil as B will now be + (positive) to the battery and C will be – (negative) to the breaker points.

6.   Reconnect battery and try ignition switch, be ready to turn off if a problem.

7.   Swap the + (positive) and – (negative) of the clock (check with a volt meter) and check the polarity of the Amp meter

8.   Your +(positive) earth radio is now of no use and you can sell it on Trademe, Ebay; buy a modern ICE for your pleasure.

9.   Check the wiring of your cigarette lighter socket as this will now be reversed and any items you had used before might need their polarity checking or changing. Be prepared to replace fuses as there are bound to be some items you've forgotten to reverse.

 

Why not consider a Dynamo/Generator to Alternator swap while you are at it. http://www.galeforcezephyrs.com/linked/generator%20to%20alternator.htm

 

Disclaimer: The advice and guidelines given in these articles are given in good faith. The owners and managers of the Galeforce Zephyr site will take no responsibility for any injuries or loss sustained while carrying out the described tasks and procedures or any consequences arising.  Please read the Safety First Article

 

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