Since I'm a newbie on light bulb collection, I have several questions that confuses me:
1. Does a standard B22 socket compatible with a standard LPS lamp base (BY22D)?

2. I nearly blow up the capacitor when I tried to fire up my 50W MV (wrong wiring), how should I wire those up? I don't want to fry my VS ballast

3. What will happen if I connect a F4T5 to a double-ended MH ballast? Will the bulb explode or just loses vacumm (in general condition)?

*Sorry for my crappy english, as I'm not a native english speaker.

Wellcome !

1. As far as i know there are 2-pin and 3-pin bases, 2-pin (same base exactly) used for incandescent and LPS, and 3-pin for mercury lamps (older ones ?)

Im not from a places that uses any type of B22 sockets so can't tell from experience,only from what i read so far



2. Where are you from ? (voltage)

 - In 240v systems the capacitor is not required at all. Wiring is - Live----Ballast----Lamp----Neutral. Capacitor can be used for power factor correction, in which case it is conected to Live and Neutral so getting straight 240v independent of the ballast/lamp circuit

 - In 120v systems the capacitor may or may not be required. Some balasts are HX with Live(Hot), Neutral and Lamp wires. You apply 120v to Live and Neutral, and connect lamp to Lamp and Neutral. Ballasts requiring a capacitor vary - Some have plain 2 wires from the ballast to connect directly to capacitor, in others the capacitor may be in series with the Lamp wire

240v capacitor just have to be there to do PFC. If the capacitor is bad the lamp will work the same, but some capacitor failures may be quite explosive (this will happen with the capacitor connected to the line directly as well, if your capacitor is of the correct type and ratings and it still blew, it must have been failing anyway)

120v ballasts with capacitor use the capacitor for actual work in series with coils, so they require quite strict capacitor value or else you are off into resonances, wrong currents and so on. They also may require higher voltage capacitor. Make sure the capacitor you used is the proper values, wired properly, and that the ballast you used does ned a capacitor. And failing capacitor can be the problem as well



3. Probably light very brightly for a while and then loose vacuum, possibly explosively (as the pressure rises with temperature....)

1. I have used a normal plastic B22 socket for LPS lamps. I am still not sure if they are identical, because the lamp was very hard to insert (perhaps I even used a knife to "trim" the socket slightly to make it easier to insert and remove lamps). I was never able to get a real BY22D socket for comparison. But a cheap plastic B22 does seem to work well enough.

I've also used the cheap plastic B-22 sockets for LPS lamps and they do fit but depending on which one you get you might have to trim off some of the plastic to get the lamp to fit. I can post some pics of the B-22 socket vs a real BY-22D LPS socket if you want. 

I've had problems getting SOX lamps to fit standard sockets too so I do wonder if there is a difference. Usually the pins jam on the lobes of the socket with the base flange jammed against the socket so you can not turn the lamp to locate the pins. I've had this with ceramic sockets and plastic E27 to B22 adaptors. A normal bulb or CFL usually fits fine albeit sometimes still a bit stiff if the springs are strong.

The socket I fitted into my LPS wall pack was a right to fit the lamp into at first but with a few uses the excess ceramic has evidently been removed. I was a bit worried about breaking the bulb with the effort needed to rotate it! Another reason I prefer E27 sockets


BG

Did the ceramic break against the glass of the lamp ? Thats bad cause it can leave a scratch in the glass, causing the lamp to shatter later

No, it was the shaft of the cap itself fouling the lampholder as the pins weren't in far enough to clear the lugs in the socket. The pins may be set further up on the SOX lamps, I'll have a proper look later at two BC lamps together (a SOX and a GLS) to see if there's any noticeable difference.

The lamp pins may have scraped off some excess ceramic from the lugs.


BG