I have a few igniters from HPS streetlights that are dead. Instead of going and getting igniters for $15-$20 each, does anyone have a schematic or parts list I could use to fix it?
Thanks!

What type of ignitors are they? I don't have a schematic. But I do have about 12 of these open ignitors that I use to replace parts of my dead pillbox ignitors. (Right in the pic). Could you decipher the schematic?

They are the open type, if you can't find a schematic, do you know the parts list?

Surprisingly difficult to find schematics on the web. Sorry for the poor images.

Well, the better quality picture of the SN57 you may find here.
It is for 230V circuit
The R1 and R2 would be around 330kOhm, but the R2 is assembled from multiple series resistors to make sure it can handle the peak ignition voltage (so e.g. 3x 100kOhm for R2, 330kOhm for R1, when you use DB3 as the D1 diac, the R3 would be about 27kOhm), the C2 would be about 10nF/63V, triac some 800V type, C1 in the described range, but rated at 1kV.
It is designed for the series choke ballasts with the tap in 20% of the winding from the line input.

The two others use a 210V SIDAC, about 47 to 100nF capacitor (the top one), a 10kOhm/5W resistor.
The "superimposed" type uses a ferritte pulse transformer with about 30mm core. About 200 turns on the secondary (4kVpk), 10turns on the primary (200Vpk). Sometimes an additional ~10..22nF is used parallel to the resistor (to create a short return path for the HV pulses). Both capacitors are at least 630V rated.
The last utilizes the ballast winding to act as the pulse transformer, it requires tap in 1/20 from the lamp end. The design then  needs some 10's mH inductor in series with the resistor, as it is exposed to the full peak voltage, so the resistor will eat most of the pulse energy out (and the pulser won't work)

The last one is then used for 120V series choke as well, there the SIDAC would be of a 100V type, the capacitor is about 330nF, resistor 4.7kOhm, the inductor is the same as with the "230V" version (used with the transformer ballasts in the US as well).

Increadibly, no one has ever made a schematic of a simple HPS ignitor (or google sucks), so I'm uploading a pic with identifying parts or numbers. I deleted the crappy & wrong web pics I posted before. This is a General Electric Cat. # 35-216700 - 01 starter (stamp on the plastic, 35-216700-22 on sticker). Simple circuit & common parts. I'm not sure, the diode thing is some voltage transistor, Zener diode or a SIDAC as medved mentions.

Note that I have also used these parts with 35w HPS. Also note that this ignitor is for N.American 120 Volts HPS ballasts for 52-55V lamps, not 240v European nor for HPS ballasts of 250-400watts, nor semiparallel ignitors (Philips SN57). Further note, the ---A--- in the schematic on right is the ignitor to lamp length (mustn't exceed about 3feet for most wiring).

@light*plus:
What about
http://pdf.datasheetcatalog.com/datasheets/270/388260_DS.pdf (datasheet for a K1100G sidac)
figures 9.3 and 9.11?

The "120V" circuit (for the US 55-60V HPS lamps) it is the K1100 type, for the 230V and the 70..100V US lamps it is the K1200 type

Will the 52-55v igniters work on 120v HPS reactor ballasts?

Yes, 52-55 is the arc voltage of the lamp.

 Went to my local parts shop and I couldn't find much. Where do you find the parts? There were no diodes that matched the one you used and no capacitors.
George, could you give me a bare parts list with what each of the components are and what they are called or like what you would go and buy?

I don't think all the parts would be available in shops like RadioShack (I mean what it used to be 12 years ago or earlier) or so, you will more likely find the complete ignitor...
You may suceed with distributors like Farnell/Newark, RSComponents or so.
Examples (for the 120V series reactor; from Newark)
SIDAC: http://www.newark.com/nte-electronics/nte6419/sidac-125v-axial/dp/29C4770
Resistor: http://www.newark.com/nte-electronics/5w233/resistor-wirewound-3-3kohm-5-axial/dp/33C8917?ost=3.3kOhm&selectedCategoryId=&categoryId=800000005308
Capacitor: http://www.newark.com/epcos/b32521c3474k/capacitor-polyester-film-0-47uf/dp/20C9889
Inductor: http://www.newark.com/bourns-jw-miller/5800-103-rc/high-current-choke-10mh-50ma-10/dp/63K3813

Usually, from what I've repaired (I've repaired about 6 ignitors), the resistor is what's burned. So simply test the resistance of that, but isolated (remove from bad circuit).

You'll find all the parts online; it's now rare for dedicated electronic shops to have precisely what you need. The parts are:

16 milliHenri Inductor
3300 Ohm power-resistor
0.47 microFarad 200V to 240V capacitor

That SIDAC cutoff voltage diode should be definitely be searched for online. I've taken a pic of another SIDAC chip. As you see they come in a variety of types.

I can spare 2 of these wafer ignitors. PM me with exactly what you need. I'll snip off from wafer with the parts only, or at least the connection tabs. Because as you know if the packet is over 5mm in thickness it's a parcel according to CanadaPost.

The ignitors are not that much sensitive for the component tolerances.

The SIDAC triggering voltage has to be 80..100% of the rms OCV of the ballast, so with the 120V fed series reactor it means about 90..120V.

The values are a result of an optimization involving:
Together with the resistor and capacitor it should fire near or a bit earlier than the mains peak voltage, so the lamp ignites at the phase where would be the current zero crossing when just ignited (nearly 90deg phase shift due to low drop of the cold lamp), in that way the "magnetic" inrush transient gets minimized.
That should be with a minimum power dissipation on the resistor when the lamp is then running (a 55V 60Hz square wave) and yet the maximum pulsing energy.

At the same time it should have high marging from firing when the lamp is operating - therefore the SIDAC trigger voltage has to be well above the lamp operating voltage.

It results into an RC time constant of about 10% of the mains period and the mentionned SIDAC trigger of the 80..100% ballast OCV.

Found a pdf file for the K1200E70 SIDAC in above pic. Within this pdf there are good schematics for both HPS 120V & 220v circuits, as well as for metal-halide, and with values!

Alright, this electronic surplus store had some 0.47uf caps and some resistors, so I'm good on those. Now I'm on the hunt for the inductor and the SIDAC which is stupidly rare. I don't really want to order it. George, where do you find the parts for repairing yours?

I was on the hunt for a sideac, since a craptastic caster Ignitor needed one.