I have two Venture Lighting BVS-041 IMP MH ignitors. I am thinking about getting a 150w s55 HPS ballast that is just the transformer and using these ignitors with it. Will the metal halide igniters work the same as an HPS ignitor or it can only be used on metal halide ballasts?

Also, what is a BVS or BMS ignitor? Both use three wires, that's all I know.

The low voltage ignitors for the 35W S76 to the 150W S55 high pressure sodium lamps are NOT interchangeable with low wattage to medium wattage pulse start metal halide ignitors because the ballasts for low wattage North American high pressure sodium lamps except for the 150W S56 high pressure sodium lamps have an OCV of 120V whereas the pulse start metal halide ignitors are designed for ballasts with an OCV of around 200V-277V for the low wattage and medium wattage pulse start metal halide lamps. In addition, even though the medium wattage high pressure sodium ignitors are designed for a somewhat similar ballast OCV compared to low wattage and medium wattage pulse start metal halide ignitors, the ignition pulse voltages for the high pressure sodium ignitors are usually lower because high pressure sodium lamps usually have a lower starting pulse requirement compared to pulse start metal halide lamps.

Does that also apply to high wattage PSMH and HPS ignitors that they also aren't interchangeable? I tried a PSMH ignitor on a 400w HPS CWA ballast and it seemed to work like the original one.

I think the ignitors designed for 1000W M141 pulse start metal halide ballasts and 1000W S52 high pressure sodium ballasts are interchangeable because of the fact that those ballasts have a similar OCV somewhere between 380V and 480V. However, be careful with using semiparallel pulse start metal halide ignitors on high pressure sodium ballasts since their higher voltage pulses might damage the insulation of high pressure sodium ballasts. If you do want to use an ignitor to reliably run high pressure sodium ballast compatible pulse start metal halide lamps, your best bet might be to use a European 220V-240V superimposed ignitor for the medium wattage high pressure sodium ballasts and the 380V-415V superimposed ignitors for the high wattage high pressure sodium ballasts since those ignitors do not use the ballast’s coils to assist with starting like North American semiparallel ignitors do. However, the wiring diagram between European superimposed ignitors is quite different from that of North American semiparallel ignitors. Unlike our semiparallel ignitors that need a specialized ballast tap for proper operation, European superimposed ignitors do not need those specialized wire taps, which means they can be used on mercury vapor ballasts to run pulse start metal halide lamps and high pressure sodium lamps on them.