Books - auto electrics - why coils work - why condensers don't - solar panels are good

[anthonym]

just taken delivery of a few, wondering what we think about each of them?

 

Electrical and Electronic Systems ISBN 6-99414-00462

Haynes Manual... 2006

 

How to Diagnose and repair Automotive Electrical Systems ISBN 9-780760-320990

Tracy Martin 2005

 

Automotive Electrical Manual ISBN 9-781850-106548

Haynes TechBook 1989 2000 & 2004

 

funny.. the ISBNs are presented with more and less numbers .. very odd.

 

and the one I have been using, having discovered it already on my bookshelf, seems to be an earlier edition 1995 of the one above :

 

Electrical and Electronic Systems ISBN 0-38345-03049-9

Haynes Manual... 1995

 

Given my car under review is 1987 I suppose older books are very fine for the purpose.

 

and you may ask "why" I want such information? Because I have seen on a daily basis over 80 days how modern garage work is based on swopping out bits until it works. I desire to understand, in great detail, why my car does not work, and on occasion, why it works when it shouldn't - that most perplexing state of all.

 

For now I have two items on my agenda:

 

how to test a capacitor in in the form of a condenser user with points.

 

why opening the points fires the coil. (easy when you understand is my guess).

 

My work on the car is "roadside" (outside, no electricity (except solar panels) or heat) so I need practical weather and the time opportunity, both at the same time.

 

Nice surprise how effective are the solar panels - "one as a conditioner", one for charging - and it works much to my surprise. Started the R500 after a year, nice surprise albeit only three cylinders.

 

Blat miles this year = maybe 30. Total miles maybe 250, mostly a trip to Wybunbury, Cheshire meet where it was great to meet like minded souls. Days working on car say 90, 80 in a commercial garage with tools, equipment advice and help on tap.

 

All pleasantly part of the challenge.

 

Isn't D.I.Y. about understanding as well as making it go? Or is that just my liking of complete analysis and details?

 

Anthony

 

[Roger Ford]

why opening the points fires the coil. (easy when you understand is my guess).

Faraday's law says that a current is induced in a wire when a magnetic field changes. Doesn't matter whether it goes from nothing-to-something or something-to-nothing. So you've got a current flowing through the points, and through the low-voltage part of the coil, causing a magnetic field. When the current ceases, the magnetic field collapses, inducing a current in the high-voltage windings of the coil, and hence a spark. It's a bit counter-intuitive.

[John Vine]

Quoting Roger Ford: 

Doesn't matter whether it goes from nothing-to-something or something-to-nothing.

That's not right, surely? Lenz's Law states that the direction of the induced current opposes the flux change (or words to that effect).

 

JV

[Roger Ford]

When I say it "doesn't matter" I mean it will still induce a current. The direction of the current flow is probably different.

[irrotational]

is this the bit where you have to hold up your left and right hands (with your thumb, forefinger and middle finger sticking out) and realise no matter how hard you try you can't rotate one to match the other!?

 

It still makes no sense to me that it's impossible

[jonboylaw]

Ha ha, I remember sitting in my Electrical Field exams watching everyone doing the 3 finger spread..

I think it goes as follows:

ThuMb is Motion

First finger is Field

SeCond finger is Current.

 

 

[OliverSedlacek]

Electrickery is difficult because volts, amps and ohms are not properties we get an intuitive feel for. With experience you get familiar with the numbers, but it's not black magic. My advice is to keep your eye on the energy, as it's always conserved, although eventually it all turns to heat.

 

In an ignition system, energy is stored in the magnetic field of the coil. The energy flows in when the points are closed and the current in the coil ramps up. When the points open the current in the primary is broken, and the energy needs to go somewhere. In normal operation the energy goes into the spark, which lets current flow through the coil secondary winding.

 

If you want to check a condensor all you need is a multimeter with a capacitance capability.

[John Vine]

Quoting irrotational: 

is this the bit where you have to hold up your left and right hands (with your thumb, forefinger and middle finger sticking out) and realise no matter how hard you try you can't rotate one to match the other!?

 

It still makes no sense to me that it's impossible

Ah yes, Fleming's Left-hand and Right-hand rules --- LH for motors and RH for dynamos. Good god, they bring back memories.

 

JV

[Johnty Lyons]

Been an AutoSpark for over 40 yrs. Forget all your rules and laws and don't worry about the Ohms,Volts or Amps.

Just keep the smoke in the cct cos once it escapes yer fecked. 😬