positive ground to negative ground

[Plymouthy Adams]

no...you would accuse someone of taking advantage of you because you did not know what is needed.....?

[Los_Control]

43 minutes ago, Sam Buchanan said:

I have no formal electronics training..........can somebody come swap out this battery for me???    ?

 

Grumpy old men.......................

We can teach you, first you will need a multi meter

both black & red colored electrical tape

depending on hold down style, you may need to flatbed it to a shop and have removed .... union electricians are not allowed to do mechanics

 

When you get the hold down removed, let us know  

 

[Plymouthy Adams]

and  it may come down to whether or not you tag number ends in an even or odd number.......

[maok]

4 hours ago, Sniper said:

 

How about this then, I finished my electronics training in 1984 and have 36+ years experience.  That qualify as an expert for you?

 

It is apparent to me you know little about Ohm's law, the basic foundation of electricity and electronics.

 

What determines Voltage? Current times resistance.  The wiper motor's resistance does not change so in order to change the voltage you have to change the current.  You limit the current, you limit the voltage, period. 

 

So go tell my wipers that limiting current does not work.

 

https://youtu.be/Ip-mtPqGBd4

 

Its obvious now that in your 1984 electronic training you either skipped DC motor theory 101 or it wasn't in your course.

 

I suggests you google - 'voltage and current relationship with a DC motor', or even do some experiments with a DC motor to determine the relationships.

 

Your knowledge is incomplete, Ohms laws does not work when applied to a DC motor.

 

• The four essential facts that dictate the basic properties of a DC motor: For a fixed load, the shaft speed is proportional to the applied voltage. ... The shaft torque is proportional to the applied current, no matter what the voltage. There is internal electrical resistance and internal mechanical friction.Sep 21, 2014

 

• The speed of a motor is determined by the voltage and the torque by the current. If a motor is running at a certain speed with a constant torque and the load increases, the current will increase and so also the torque to maintain the same speed.May 8, 2014

[Sniper]

Once again, your theory fails when reality comes to play.  My video explicitly debunks your statements.

 

Go read about using current to control a DC motor's speed.

 

https://muniracademy.com/speed-control-of-dc-motors/

 

 

Edited July 13, 2020 by Sniper

[maok]

30 minutes ago, Sniper said:

Once again, your theory fails when reality comes to play.  My video explicitly debunks your statements.

 

Go read about using current to control a DC motor's speed.

 

https://muniracademy.com/speed-control-of-dc-motors/

 

 

 

Do you understand that the DC motor you have is a series wound, from your link,

 

2)     Series DC Motor:

DC series motor is controlled by the Armature Voltage method only. The problem with Armature Current and Flux method is that both of them need a change in resistance. In the Flux control method speed is inversely proportional to resistance. While in Armature current control the speed is inversely proportional to the resistance. We insert a variable resistor in series with the armature and field circuit. The problem with the Series motor is that both filed and armature are in series. If we insert resistance for armature current then this resistance will affect the Field flux as well. As we know both the methods show different behavior of speed on changing resistance, this method is not feasible. Further, inserting a variable resistance will increase losses. We can simply control the speed by the Armature Control method. The armature voltage is controlled by changing the Terminal Voltage. The circuit will be as,

Armature Voltage Control Method on Shunt DC Motor

[maok]

This is the reason why the wiper motor turns twice as fast with 12 volts applied, the current essential is the same, actually its slight more due the slight higher friction resistance applied (from the extra speed) to the shaft from the wiper blade rubber.

[dpollo]

the wiper motor is a shunt connected unit, meaning that the armature and the field coils are wired in parallel.

the starter, on the other hand is a series wound unit.

if you limit the current flow to the field coils , a shunt motor will speed up

a series motor has no limit other than friction to its speed.    All DC motors will increase in speed if the voltage is increased.

 

most 6 volt cars except for GM were positive ground.   Lucas electrics, even 12 volt were positive ground until about 1970

the radios used were only marginally affected by reversing polarity but when solid state power supplies came into use (mid 50s) radios were polarity sensitive .  a choice had to be made and manufacturers chose to follow GM (1956 for Ford and Chrysler ) but some  British makes, including English Ford continued to use positive ground.

Edited July 14, 2020 by dpollo
more info

[frijolito]

The funny thing that you guy failed to read is that I don’t care about the wipers they are Vacuum wipers! 
I just want to switch the car to negative ground keeping the 6v

[Sam Buchanan]

6 minutes ago, frijolito said:

The funny thing that you guy failed to read is that I don’t care about the wipers they are Vacuum wipers! 
I just want to switch the car to negative ground keeping the 6v

 

This is referred to as "thread creep"........this forum is renowned for our ability to drive a thread off the rails.   ?

[Tom Skinner]

Go mix yourselves a nice strong drink gents and relax. L.O.L.

I would be the first to admit I do not know much at all about vacuum or electrical issues? 

[Sharps40]

Good gosh fellas.   Just rebuild the vacuum motors.  Put on a vacuum fuel pump (may need header mod) or an electric vac pump, and if you like add a vacuum ball/ check valve In Line.....or see if the same year dodge, Chrysler,  desoto electrics fit.  

 

No need to puff up and spur each other like horny roosters

Edited August 7, 2020 by Sharps40

[50mech]

On 7/13/2020 at 1:50 PM, Sniper said:

 

How about this then, I finished my electronics training in 1984 and have 36+ years experience.  That qualify as an expert for you?

 

It is apparent to me you know little about Ohm's law, the basic foundation of electricity and electronics.

 

What determines Voltage? Current times resistance.  The wiper motor's resistance does not change so in order to change the voltage you have to change the current.  You limit the current, you limit the voltage, period. 

 

So go tell my wipers that limiting current does not work.

 

https://youtu.be/Ip-mtPqGBd4

Well, technically the wiper motor has impedance, and it changes based on the load. Haha I'm just being cantankerous.

 

 

On 7/11/2020 at 7:02 PM, maok said:

And one failed attempt does not make one an expert.

 

Limiting the current does not slow it down,  voltage level controls the speed.

Power is the factor that will determine it's speed. 

Power ,watts, is current times voltage.

You can change the current or the voltage to change the power.

The simplistic way is to add resistance. 

That's not the best method with a motor since you want to match it's "resistance" to drop the power in half. If the motors impedance happens to be matching at the given time then both would get 6v. However It can have a much lower resistance at startup or with a load, that's impedance at work. It can be done that way and work since most of it's operation it sees a fairly average resistance.

 

Since sniper chose the words current limiting circuit, I'm guessing he probably actually built a fairly simple circuit that's designed to match the motors impedance or some other method a bit more correct than simply adding a resistor. That eliminates the extra slowdown at startup and when the wipers change direction that you get by simply adding resistance.

[Sniper]

Well, to be seriously anal, impedance applies to AC circuits not DC.  One could make the argument that since the commutator in effect chops the DC and turns it into a pseudo AC waveform it still applies.  I don't get that far into these things so much anymore and I won't argue that you are wrong about it either.

 

But as I said, theory is nice, till it hits reality and in my world reality trumps theory.  So if my circuit does what I wanted it to do that is all that matters for me.  I do need to redesign it as it does move slower than I want.  It's fine for a low speed (misty rain) setting, if I had more than one speed to choose from.  Might do a two speed redesign, but I would need a new wiper switch.  Heck, If I am going to do that I may as well go for a three speed or even a variable speed.

 

See what you did there? 

[50mech]

11 minutes ago, Sniper said:

Well, to be seriously anal, impedance applies to AC circuits not DC.  One could make the argument that since the commutator in effect chops the DC and turns it into a pseudo AC waveform it still applies.  I don't get that far into these things so much anymore and I won't argue that you are wrong about it either.

 

But as I said, theory is nice, till it hits reality and in my world reality trumps theory.  So if my circuit does what I wanted it to do that is all that matters for me.  I do need to redesign it as it does move slower than I want.  It's fine for a low speed (misty rain) setting, if I had more than one speed to choose from.  Might do a two speed redesign, but I would need a new wiper switch.  Heck, If I am going to do that I may as well go for a three speed or even a variable speed.

 

See what you did there? 

Yeah, you're right. Still dealing with cyclic inductive reactance in a motor though, which is why I guess I called it impedance. 

In any case I was just messing around.

 

Problem here is, we don't have separated arm and field terminals. Total overall resistance is unchanged so limiting current or voltage on our wiper terminal has the same net effect. Limited power. 

 

Shunt wound limiting field increases speed, assuming arm is not limited.

Limiting arm decreases speed.

Limit both and you've limited total power. Slows down.

Power in ^=power out

 

Voltage and current the motor take are tied by their relationship , we can limit the availability of either.

 

Unless we're splicing into the motor internally and changing the arm and field separately none of the speed control methods apply explicitly.

 

 

[Sniper]

You are exactly right.  So, who's going to wake everybody else up after we put them to sleep?  Lol.  I love these kinds of technical discussions.

[Los_Control]

15 minutes ago, 50mech said:

Yeah, you're right. Still dealing with cyclic inductive reactance in a motor though,

Were these words even event'ed when the flat 6 was popular?

 

Los runs back to his corner  

 

[50mech]

48 minutes ago, Los_Control said:

Were these words even event'ed when the flat 6 was popular?

 

Los runs back to his corner  

 

Was it still popular in September of 1985? I think that's when doc came up with the flux capacitor.

Might not apply to flat 6 though, not sure they can do 88mph

Edited August 10, 2020 by 50mech

[Los_Control]

This is why the 3:88 gears have been hidden from dodges .... We get the 3:73's .... but oh noes no 3:88 for us