SpudFiles

Built some low-tech combustion guns in my youth, but I'm looking at creating something a little more updated.

I have an electric BBQ ignitor that has 3 electrodes. This should allow me to create 3 separate spark gaps, correct?

In the instructions, it says that if only 1 or 2 electrodes are being used, one of the empty electrode points needs to be grounded. If I'm using all 3, is a separate ground not needed?

If anyone has pictures or diagrams/explanations of how to set up a 3 electrode electric ignitor, that would be great. In the mean time, I'll experiment with a few setups.

Thanks!

I'm a little confused, I have never heard if a grill igniter with 3 electrodes. The configuration for a 3 spark setup would be (+) -- x -- x -- x -- (-), with x being the spark gaps. Basically make sure to connect them in series, and not in parallel.

Zach1188 wrote:I'm a little confused, I have never heard if a grill igniter with 3 electrodes. The configuration for a 3 spark setup would be (+) -- x -- x -- x -- (-), with x being the spark gaps. Basically make sure to connect them in series, and not in parallel.

I think that sparker is a 3 output for 3 gaps. They use a current balancing transformer, so an unused gap needs to be grounded to provide current to the other gaps. Follow the directions. It has 3 outputs, one bbq frame ground and each gap sparks to ground if it is the one I am thinking of.

It operates much like a two tube light balast. With one tube out the other one gets little current and goes very dim.

Here's a pic of the one I have... 3 electrodes (meant to accomodate front, side, and rear burners.)

Do you have a part number or a link or a photo of BBQ sparker?

How it should be wired depends on if the sparker is meant to use the three gaps in series or parallel. If all three are meant to use a common ground (probably the body of the BBQ) then that means the sparker has three independent spark generators. If the sparker has say three wires + ground wire (or the sparkers body) then that suggests three independent sparks.

If the sparker has two wires (one of which might be a metal part on the sparkers body) then the gaps are supposed to wired in series.

slogfilet wrote:Here's a pic of the one I have... 3 electrodes (meant to accomodate front, side, and rear burners.)

That one is like I mentioned above. There are 3 gaps. They all spark to ground. A current balancing transformer ensures all 3 gaps get nearly equal current.

Of course everybody and their brother is trying to patent applications for a transformer.

http://www.patentstorm.us/patents/70752 ... ption.html For example balancing the current through several fluorescent tubes in a back light.

As far as installing it to a launcher, all you have to do is hook the middle electrode with one of the outward electrodes. The other (which should be protected) can either be filled in with epoxy or simply left alone. When I installed one on my combustion, I just didn't mess with it.

It makes sense to me when using only 1 or 2 of the electrodes:

For 1 electrode, a ground wire is attached from electrode socket 2 to the bbq, and socket 3 is unused.

For 2 electrodes, the 3rd socket is ground.

But when using all 3, how is ground supplied? I'm an electronics noob, so it might be obvious to someone else.

As I said, you only need to use the middle one and one on the edge. The third one is not needed for our applications.

Thanks for your help... looks like we were typing at the same time.

I think just using 2 would be fine. 2 spark fronts would be reasonable, with some sort of conductor between them, creating 2 gaps.

And wow, that help came quick! I always brace myself (and don my flame retardant suit) after a first post on a new forum, but you guys are great.

Are you familiar with how a spark strip or spark gaps work? If not, check wiki (in the upper right corner).

That wiki is awesome. A spark strip is exactly what I had in mind!

Things in the spud gun world have come a long way...

I have the same one on one of my cannons.

It has three electrodes, the middle is the ground and the outer ones are sparky.

For the money USG's 30Kv ignitor is easier to use. It has mounting holes and a separate circuit for adding in a switch. The three prong one here had to be modified with a dime to remote trigger and required a ginormous 7/8 hole to mount it into.

Thats a nice looking sparker. Make sure you do it proud by making a nice cannon to match!

I wouldn't bother with the spark strip (aka "chamber short"). You've got a source of three independent sparks, just use it that way. The spark strip is a way to get multiple sparks from a single spark source.

Just install three sets of fine threaded (so they don't leak) drywall screws so that each set almost meets (1/8"~1/16" or so gap) near the central axis of the chamber.

One screw of each set can be connected together and returned to the sparker's ground contact. The other three screws get a wire from one of the spark outputs.

Usually folks would try to position the sparks evenly along the chamber's length. If the chamber is L inches long then for three sparks:
#1 at L/6 from the back of the chamber.
#2 at the center (L/2) of the chamber.
#3 at L/6 from the front of the chamber.
This layout will get the flame fronts to meet at about the same time the front and rear flame fronts burn out at the ends of the chamber.

It would be best if you can keep the 3 HV wires going to the spark gaps separated from each other by at least a half inch or so. Basically, you want the air gap to augment the wires' insulation.