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the resistor is limiting the current.

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Old 10-15-2020, 03:59 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #21 (permalink)
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I only know what I need to know with electricity.

But I think capacitors are amazing.
Old 10-15-2020, 04:03 PM
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although looking at the ciricuit, and its been a loooooong time since I have thought about basic ELEC, the LED will light with the SW in both positions.
although momentarily off until the CAP charges up. with no resistor in series with the CAP and no known value, it would probably charge almost instantly.

in electronics wire is normally not taken into account.
It is possible it "could" be considered in very low voltage circuits.

the LED IS a load. it does have a voltage drop across it. diodes are normally about .7v, I think an LED may be higher.
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86 930 94kmiles [__] RUNNING:[__] NOT RUNNING: ____77 911S widebody: SOLD
88 BMW 325is 200K+ SOLD
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01 suburban 330K:: [__] RUNNING: [__] NOT RUNNING:
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Old 10-15-2020, 04:08 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #23 (permalink)
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Originally Posted by theiceman View Post
the purpose of the resistor is to limit the current going through the led.. keeps circuit current low.. forward biased diodes have very little resistance and require very little current to light, without the resistor the higher current flow would burn it out .
Are you even looking at the same diagram?
The only thing in the entire circuit is the capacitor and the LED.
There is no separate resistor !!
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Old 10-15-2020, 06:06 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #24 (permalink)
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Originally Posted by sugarwood View Post
https://learn.sparkfun.com/tutorials/capacitors/all

There may be others who are interested in the next step of reading diagrams.
Is anyone willing to post and explain a very basic electrical diagram relating some some simple aspect of the 911?
Like a window motor, for example

I don't want to steal this other users post, but he has a good schematic of the window motor circuit. Power Window Switch Schematic.

If you follow the lines, you can see the traces apply either forward bias (positive voltage) to the motor or reverse bias (negative voltage). The switch just changes the polarity. DC motors are neat because they can run forward or in reverse just by this simple change. They are really not much more complicated than that for a basic intro.

These cars were developed in a pretty basic age as far as car electronics go. I think the most complicated issue is knowing where all of the wires go and which circuits are tied to which. The actual functioning of the circuits is pretty straight forward.
Old 10-15-2020, 07:17 PM
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Quote:
Originally Posted by Bill Douglas View Post
I only know what I need to know with electricity.

But I think capacitors are amazing.
When I was in college my roommate was a EE. One day I was sitting in the floor of our room studying. My roommate was sitting near me building something with a pretty big array of capacitors. I was positioned between him and the door to our room.

All of a sudden I heard a pop and he jumped over me like an Olympic hurdler and ran out of the room like he was on fire. I found him sitting in the hall and his lips were blue.

And that’s why to this day I think it’s helpful to have an EE friend around to teach the rest of us about electricity.
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Old 10-16-2020, 10:15 PM
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Quote:
Originally Posted by GAJon View Post
I don't want to steal this other users post, but he has a good schematic of the window motor circuit. Power Window Switch Schematic.
.
Excellent post.
First reply that is actually on topic.

The battery wire goes through 2 fuses, #17 & #18
Why is one yellow and one red?

Wire then goes into the J relay.
Ignition switch closed, power flows through 85/86,
which then closes 30/87, allowing current to flow to window switch E39/E41.
Finally reaching the window motor at V15.




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Old 10-17-2020, 06:01 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #27 (permalink)
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Originally Posted by GAJon View Post
If you follow the lines, you can see the traces apply either forward bias (positive voltage) to the motor or reverse bias (negative voltage). The switch just changes the polarity. .
Can you explain how you read this? How does the diagram show the 2 different states a window switch can hold?

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Old 10-17-2020, 06:07 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #28 (permalink)
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