Author Topic: Power Box  (Read 6047 times)

Offline Brian Rupnow

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Re: Power Box
« Reply #15 on: January 27, 2014, 04:47:21 PM »
Bummer!!! The red light doesn't work!! oh well, I have enough other stuff to keep me busy for the rest of the day---

Offline Brian Rupnow

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Re: Power Box
« Reply #16 on: January 27, 2014, 07:35:10 PM »
I just took my team of Huskies and mushed down to my nearest auto parts store, and found a red indicator light with two terminals, and an illuminated switch with 3 terminals. I haven't wired anything much since I built my hot-rod ten years ago, but this has got me thinking. If I put the two terminal light in series with the hot wire that goes thru the switch to the coil, the light will only be on when the points are closed and the current is flowing. The light will be constantly blinking on and off as the points open and close.--I don't want that. Plus if its wired in series, the light itself is going to act as a flow restraint to current running to the coil. If I hook the light up in parallel with the coil, it will be almost the same--no current can flow--period--until the points are closed and let the current flow to ground--and when the points are open, it will still be an open circuit, causing the light to blink on and off as the points open and close, but since it is in parallel with the coil it won't act as a current gate. My original thinking was hot wire from battery to switch, to light, to coil, thru wire which leads back to points, thru the points to "ground" and a jumper wire from the engine base back to the negative side of the battery. If I don't want my light flashing on and off as the points open and close, maybe I have to run a relay. This will (I think) make it necessary for a third wire (not counting high tension coil wire) to run from the relay to ground. So--current travels from battery to switch, to light, to pull down relay, then back out this extra wire back to negative side of battery. Hot wire from battery is split before switch and runs to relay--one side of relay is always "hot". So--when switch is turned on, light is lit, relay is "pulled in" and wire runs from other side of relay back to negative side of battery. Then there is a second circuit which basically is a hot wire from relay to coil that is only hot when switch is on and relay is "pulled in". Current travels thru coil, then to points, then to ground, then thru jumper wire from engine back to negative side of battery. Light will be lit constantly as long as switch is on and current is flowing thru relay to keep it "pulled in". Current will flow to coil and engine will run as long as the relay is pulled in. When switch is turned off, current no longer flows so light goes off, relay is no longer "pulled in" so reverts to open circuit---No power gets to coil so engine stops. Have I got this right or am I overthinking it

Offline Brian Rupnow

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Re: Power Box
« Reply #17 on: January 27, 2014, 10:24:37 PM »
Guys--I was overthinking this one. I can do it without a relay. All I will need is the extra wire to return the hot feed from the light back to the frame of my engine which will be grounded to the negative side of the battery. Crap-o-cad sketch attached----


Offline ColH

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Re: Power Box
« Reply #18 on: January 28, 2014, 05:20:38 AM »
Hi Brian

If you connect the non switch side of the lamp to the battery negative you won't need an extra wire to the engine frame.

You will then have the following wires:
-ve coil to the points
engine frame to Battery negative
high tension lead to the plug.

Col
ColH

Offline Brian Rupnow

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Re: Power Box
« Reply #19 on: January 28, 2014, 11:29:09 AM »
ColH--It makes no difference if the wire from the non switch side of the light runs out to the engine frame or to the negative post on the battery. It's still a third wire running out from my "power box".---Brian

Offline Brian Rupnow

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Re: Power Box
« Reply #20 on: January 28, 2014, 01:35:51 PM »
After gathering up all my parts for the power box, I couldn't decide just how to arrange things. I need room for a coil, a red indicator "power on" light, a switch, and storage for my wires. This morning I woke up at some heathenish hour and couldn't get back to sleep, so I got up and laid it all out on CAD. Haven't decided just what I'm going to do for a latch or a handle, but they shouldn't be a big deal. I think this looks pretty good considering I am working with a recycled "box". I might have to put some insulating rubber between the end of the coil and my light and switch, but then again, I might not.



Offline Brian Rupnow

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Re: Power Box
« Reply #21 on: January 30, 2014, 09:23:36 PM »
The power box is finished. I have reached a point where I didn't want to cobble some wiring together to try and start the opposed piston engine, so I took today and completely finished the power box. There are two pics of it with all its wires hanging out. I have not shown the one wire with an alligator clip on each end that connects the engine frame to the negative side of the battery.--Mainly because I had one red alligator clip and one black one, and that particular "jumper" should never be hooked to the positive side of the battery---so I painted the red alligator clip black and now its hanging in the furnace room drying. I have also shown a picture of the box closed up with all of the wires tucked away inside of it. The last 2 1/2" of coil wire is glued inside a 0.335" diameter wooden dowel, with bare wires showing at the end which inserts into the coil. That way I can insert it from outside the box and not have to be terribly concerned about it going into the hole in the end of the coil. I tried to find a hardware store handle, but they didn't have anything that would fit, so I made my own handle. I bought a "draw down" latch, and for once I actually got the holes drilled in the right place. If you have ever installed one of those miserable things, its almost a magic trick to get the two halves so that they actually do "cam over" and draw the lid down tight and stay latched. I just picked up 2 or 3 days of engineering work this morning, so the start up of the opposed piston engine might get delayed a day or two.---I hate to turn away work---that's what buys all my machine shop stuff!!!







Offline cfellows

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Re: Power Box
« Reply #22 on: February 03, 2014, 06:21:10 AM »
So, Brian, in view of the (lack of) success I seem to be having with hall sensors, I think  am going to go back to points & coil.  Here is my version of your power box, which I think I will rename Ignition Box if you don't mind...  :)



I will have an RC type rechargeable battery inside the box as well as the condenser.  I think that will leave me with just 3 wires from the box to the engine.  Does that look about right?

Chuck
So many projects, so little time...

Offline Brian Rupnow

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Re: Power Box
« Reply #23 on: February 03, 2014, 12:52:17 PM »
Looks very good to me chuck. I can't tell from your schematic, but I always mount my condenser right beside the points on the engine.---Brian

Offline rick41

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Re: Power Box
« Reply #24 on: February 03, 2014, 04:40:22 PM »
Brian,  I made a similar "power box" for my hit and miss engine.  One thing I added was a three way switch to allow terminals for charging the battery without opening the box.  Center position was off.  Left position allowed charging while the right position was for powering the engine.  Otherwise, the only way to get to the battery was to remove the bottom which was held by four screws.  The engine was mounted on the top of the box.

Rick

Offline Brian Rupnow

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Re: Power Box
« Reply #25 on: February 03, 2014, 06:08:51 PM »
Rick--I'd have a heck of a time getting that 12 volt boat battery into the box----

Offline rick41

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Re: Power Box
« Reply #26 on: February 03, 2014, 07:53:48 PM »
Brian, I guess I didn't look close enough to see the 12 volt battery.  I was assuming that the "power box"  would be a self contained unit.  Mine uses a 6 volt automotive coil and a rechargeable 6 volt sealed gel battery of the type used in emergency lighting systems.  The reason I chose 6 volt is because the 6 volt gel battery is cheaper than the 12 volt gel battery and 6 volt automotive coils are readily available at the auto parts stores. The 6 volt system delivers plenty of punch for my little engine.  My unit is 7"W x 12"L x 5"H with the engine on the top.  I enjoy following your build threads.

Rick