HT 6v Charging System w/- ground

[sofasurfer]

How do you determine the correct orientation of the components in the circuit (positive and negative wise)? It is not clear in the mockups.

EDIT::
I misunderstood post #16. Now I see that it tells how to determine orientation (polarity) of the rectifier diode. But the others are still unclear.

 

[Ode]

Does anyone have any thoughts about using a Power Wheels "Power Patrol" battery for this application? It's a 6 v, 4.5 ah lead acid battery. The physical size seems small enough. Would the 4.5 ah rating, which is higher than the originally mentioned 1.3ah item, suggest that additional charging might be needed? My bike isn't run for more than 45-60 minutes at a time, twice a day. It's also fitted with a std. 6v, 3w generator, which could supply a small amount of additional juice to the white wire source. For the light itself, I'm thinking of using a std. 6v, 15w head lamp from a vintage scooter.
(the battery is eBay # 280340681068 B.I.N. at $15.95 with free shipping)

Ode

 

[loquin]

ref the attached sketch to get an idea of the polarity associated with diodes.

 

[sofasurfer]

In regard to using batteries from various sources...
We have a place near here called "BatteriesPlus". They have it all. I just bought my 6V 1.3ah battery from them. It literally fits in the palm of my hand with room to spare. $12.99. They had a 5ah for about $15. Try them out or I am sure there are other battery companies near you that are just as good.
EDIT::
I just looked at you're battery. Pretty similar in size. O well. Thought I would give my viewpoint, even though it may not be needed.

 

[sofasurfer]

Hey Lou. I sure appreciate it but I need to be led by the hand. Does anode and cathode mean negative and positive? I can follow the path of the juice through the circuit (pretty sure anyway, but anode and cathode...?

 

[sofasurfer]

If it ain't one thing its another. Referring to post #19, I attached the striped end of the recitier diode (276-1141) to the white wire. Then when I grounded the other end to the motor the motor died. So I then did it vica versa. I attached the non-striped end to the white wire and when I touched the other end to the motor the motor again died. That ain't right is it? Whats up?

 

[sofasurfer]

Ok. To review, in my last post I did the test in post #19. I tried the rectifier diode in both directions and my motor died. That is not whats supposed to happen I don't think.

Next, I assembled the circuit without attaching it to the bike (1st photo).
After a few minutes the resister started getting very warm. Woops! I then removed the fuse so that my mockup would not burn up.

Now, if you look at the 2nd photo you will see a closeup of the busebar.
I experimented with the battery positive and my multimeter and found that voltage does go through the rectifier diode (from right to left) in the orientation that it is in but if I turn it around it would not. Therefore white wire will be able to supply voltage.

I have not tried turning the zener diode around because I have not been told if I can do that without ruining it. I can only assume that it is the reason why voltage is flowing to the resistor.

By the way, right now my battery is reading 6.36 volts on its own. When connected to circuit as in 1st photo it is reading 5.88 volts.

In both of my diodes (rectifier and zener) the stripe is on the left.
Should I turn my zener around.

Sorry for the long line of questions.

EDIT::
I did some reading and it seems that I need to turn my zener around. The voltage must travel from cathode to anode. But I need some verification from you. Please?

 

[loquin]

IF you reverse the diode (changing from a positive to negative ground,) you also need to reverse the zener diode (and the battery.) (else, the zener acts pretty much as a short to ground, and does no regulation at all - all the voltage is dropped across the resistor.)

Now. Regarding the resistor. I've seen reports of unloaded voltages in the 20+ volt range when the motor is revving. This means that with the zener dropping apx. 7 volts, the resistor has 13 volts (or more) across it. P=e*e/r, so the power dissipation of the resistor could be 17 watts, or more... (assuming the polarities are OK.) Which explains why the 10W resistor is getting hot.

 

[loquin]

Hey Lou. I sure appreciate it but I need to be led by the hand. Does anode and cathode mean negative and positive? I can follow the path of the juice through the circuit (pretty sure anyway, but anode and cathode...?

The way I remembered anode/cathode with diodes is this; the anode is on the arrowhead side. Both start with 'A' ...

I included the terms as a reference.

Now. re current flow from positive to negative. With standard diodes, the arrow DOES point in the direction of the conventional idea of current flow. (NOT electron flow, mind you, but, that's fodder for another discussion!)

Now, when dealing with ZENER diodes, there's another mindset involved. A zener diode is essentially a diode with a known reverse breakdown voltage. It's used as a voltage regulator, as, when wired 'backwards,' when the voltage across it rises above the 'breakdown' voltage, it's resistance drops, and it allows the current to flow through it, backwards, at that breakdown voltage. As the voltage rises and falls, the resistance of the zener changes to keep the voltage across it at it's rated voltage.

From a wiring viewpoint, the zener is thus wired 'backwards' when compared to a normal diode.

 

[sofasurfer]

Lou.
Regarding the diodes. Both are currently installed in the same direction. The rectifier is allowing voltage to pass through but the zener is ALSO allowing voltage to pass through to the resistor since the resistor is getting hot when the battery is hooked up. So I am thinking the zener needs to be turned around so that current does not pass through until it gets to the excess voltage .