Negative Thinking

[avanparys@viperlink.net]

I was wondering if anyone who has converted their vehicle from positive to negative earth (ground)would share the details on how to accomplish this. I have read a site at http://www.hendrixwirewheel.com/polarity that gives a description (using an Austin Healey as the an example), but was curious if there is anything else required on a TC. VR - Terry Van Parys Charleston S.C.

[Stan Kurzet]

Thinking positive, anything can be done for a price. The most expensive problems will be the starter which will have to be rewired or replaced as in it's current form it will try to start the engine such that there will be 4 speeds in reverse and only 1 forward. Also, the generator will produce the wrong polarity for your newly wired battery. Depending on type, the fuel pump may or may not require modification. If the incentive is to have a radio installed, it would be easier to use a shirt pocket portable with earphones. The racket a C makes is incompatible with listening via speaker anyway. Cheers, Stan TC 7382 & 2569

> I was wondering if anyone who has converted their vehicle from > positive to negative earth (ground)would share the details on how to > accomplish this. I have read a site at > http://www.hendrixwirewheel.com/polarity that gives a description > (using an Austin Healey as the an example), but was curious if there > is anything else required on a TC. > > VR > - Terry Van Parys > Charleston S.C. > > > > > Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/ > >

[Dwyer]

Stan Which way round the field windings are connected to the armature determines the direction of rotation of the starter, so polarity won't alter its behavior. This problem only occurs in small motors using permanent magnets for the field. The reversed battery will repolarise the dynamo field instantly, so no problem there either. The fuel pump will only be affected if it has been transistorised. The ammeter will read backwards, but this can be corrected by swapping the connections. In short there is no problem to reversing polarity as long as the car contains ##no electronics##. This isn't just my theory. Someone fitted the battery in positive-earth mode into our J2 a few years ago: it made not the slightest difference (except to the ammeter). If it suits you do it. Regards Dave Dwyer J2, TA, TC

[mrbadger]

This is all correct. The leads to the coil should also be reversed but what would be the reason or advantage??? A positive thinking Badger Dwyer wrote:

> > Stan > > Which way round the field windings are connected to the armature determines > the direction of rotation of the starter, so polarity won't alter its > behavior. This problem only occurs in small motors using permanent magnets > for the field. > > The reversed battery will repolarise the dynamo field instantly, so no > problem there either. > > The fuel pump will only be affected if it has been transistorised. > > The ammeter will read backwards, but this can be corrected by swapping the > connections. > > In short there is no problem to reversing polarity as long as the car > contains ##no electronics##. > > This isn't just my theory. Someone fitted the battery in positive-earth mode > into our J2 a few years ago: it made not the slightest difference (except to > the ammeter). > > If it suits you do it. > > Regards > > Dave Dwyer > J2, TA, TC > > > > Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/

[Frank O_ The Mountain]

In a message dated 4/3/01 11:46:24 PM Pacific Daylight Time, skurzet@msn.com writes: > Not true, starter motors are series wound motors and care not for polarity....only the generator needs a change and that is just a short flash of the field coil with the new polarity...it will then reverse its residual magnetism and from then on began charging in the opposite direction. On a TC, you also need to reverse the leads on the ammeter or just remember that positive is negative and negative is positive....clear as ? Terry

[Stan Kurzet]

You are absolutely right. After recalling that starter motors are series connected to maximize locked rotor torque, they do not care about polarity. I know the Brits put the steering wheel on the wrong side of the car to make it easier to drive on the wrong side of the road, but a series wound motor is going to behave the same as it does here in the colonies despite the fact that Maxwell was an Englishman. Cheers, Stan TCX2

> > Which way round the field windings are connected to the armature

determines

> the direction of rotation of the starter, so polarity won't alter its > behavior. This problem only occurs in small motors using permanent magnets > for the field. > > The reversed battery will repolarise the dynamo field instantly, so no > problem there either. > > The fuel pump will only be affected if it has been transistorised. > > The ammeter will read backwards, but this can be corrected by swapping the > connections. > > In short there is no problem to reversing polarity as long as the car > contains ##no electronics##. > > This isn't just my theory. Someone fitted the battery in positive-earth

mode

> into our J2 a few years ago: it made not the slightest difference (except

to

> the ammeter). > > If it suits you do it. > > Regards > > Dave Dwyer > J2, TA, TC > > > > > > > Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/ > >

[Crystal Brenner]

Now Stan...we all know the TABC steering wheels are on the RIGHT side not the wrong side, and in the early days of the motor car they were on the right even on those made in the USA...so lets not have any more negative thinking....lets ALL try to be positive...OK ! Cheers, Crystal and John TB#0398

----- Original Message ----- From: "Stan Kurzet" skurzet@msn.com> To: "Dwyer" jasper@enternet.com.au> Cc: "MG TABC List" mg-tabc@yahoogroups.com> Sent: Wednesday, April 04, 2001 2:11 PM Subject: Re: [mg-tabc] Negative Thinking > You are absolutely right. After recalling that starter motors are series > connected to maximize locked rotor torque, they do not care about polarity. > I know the Brits put the steering wheel on the wrong side of the car to make > it easier to drive on the wrong side of the road, but a series wound motor > is going to behave the same as it does here in the colonies despite the fact > that Maxwell was an Englishman. > > Cheers, > > Stan > > TCX2 > > > > > > Which way round the field windings are connected to the armature > determines > > the direction of rotation of the starter, so polarity won't alter its > > behavior. This problem only occurs in small motors using permanent magnets > > for the field. > > > > The reversed battery will repolarise the dynamo field instantly, so no > > problem there either. > > > > The fuel pump will only be affected if it has been transistorised. > > > > The ammeter will read backwards, but this can be corrected by swapping the > > connections. > > > > In short there is no problem to reversing polarity as long as the car > > contains ##no electronics##. > > > > This isn't just my theory. Someone fitted the battery in positive-earth > mode > > into our J2 a few years ago: it made not the slightest difference (except > to > > the ammeter). > > > > If it suits you do it. > > > > Regards > > > > Dave Dwyer > > J2, TA, TC > > > > > > > > > > > > > > Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/ > > > > > > > > > > Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/ > >