# Description of H1, H2, S connections on a pulse igniter

I would like to replace a piezo igniter in a small project with something that can be electronically controlled (I have created some simple hairspray-powered foam rockets, and I would like to be able to sequence several of them from a computer).

It looks like pulse igniters, like this, are relatively inexpensive, but it's been hard to find any documentation or wiring diagrams for them and I'm unsure if I understand all the connections.

There are obvious inputs for power and for a switch, but on the high voltage side there are three wires, labelled HV1, HV2, and S. HV1 and HV2 appear to come off either end of a coil, and S is a mystery.

The igniter looks something like this:

And the innards look actually like this:

HV1 to HV2 seems to generate the most effective spark, but I don't know if that's using the igniter correctly or slowly frying its innards. Can someone help explain these labels?

• Don't buy anything without a proper datasheet. The manufacturer should know and should tell you. – PlasmaHH Nov 10 '15 at 21:08
• If these are what I think they are, they begin sparking as soon as power is applied – Daniel Nov 10 '15 at 22:09
• They have a switch connection which must be closed before they will spark. The question is primarily about the outputs (HV1, HV2, and S), and what exactly each one is for. – larsks Nov 10 '15 at 23:11