Heh. When people say 'driver' to me, I always think of buses 

Well I did do it for a living for more years than I care to remember 


I'll get me coat...

an LED driver is a slightly different ball game than a discharge driver so I think LED gear ‘losses’ are minimal to nothing as far as I understand?

In the datasheet for the Philips SOX-E driver it says:

System characteristics
Rated Ballast-Lamp Power 36 W
Rated Lamp Power on SOX-E 36 W
System Power on SOX-E 39.9 W
Lamp Power on SOX-E 36.0 W
Power Loss on SOX-E 3.9 W

That seems to tell me that it has an efficiency of 36 / 39.9 = 90.2 %. A few random 40 W LED drivers I just checked have power factors ("lambda") between 90 and 95, which I think is the efficiency in %, but I'm not sure?

Yeah, a ‘power loss’ of 3.9 watts is excellent and much better than the losses you get on magnetic, wire wound ballasts. 

Hello,

I don't want to create a new thread and seeing this is the most recent post regarding Philips SOX lamps i want to ask a question. Newer had nor used these or similar lamps that require high voltage/arc to function. Recently i have bought Philips SOX-E 26W lamp (honestly hoped that I can just plug it in to 230V...). Seller or any other local store can't offer any solution to make it "work". Upon googling/watching vids/reading your posts I got even more confused - some use ballasts, some starters, in some cases capasitors were used.... I did find some electronic ballast that supposed to work with this lamp, but 200eur+ price is over the top... Is there a cheaper alternative?   

Hi and welcome to the madhouse that is LG 

Low pressure sodium lamps (SOX being just one variant), as with most discharge lamps, require a ballast to operate. The 26W SOX-E variant is an 'economy' version of the 35W SOX lamp and can be run on a 35W SOX ballast, although the best efficiency is obtained with the genuine SOX-E ballast, these can be harder to obtain, though.

I would suggest eBay or similar, a quick look on the UK site (because that's where I am..!) produced this listing which will run 35W or 55W lamps. Also, there is another slightly different type of ballast here. Both will run your lamp perfectly well.

I assume from your mention of the Euro that you are somewhere there, so I don't know if the seller will ship to your location, but it never hurts to ask.

For more information on SOX lamps (and discharge lighting in general) I recommend the Lamptech website, which is run by James, who is a member here. For an introduction to Low Pressure Sodium, see here.

Hope this helps,

Ria 

Thank you for the warm welcome  Yes I am from Sweden 
More questions coming your way 
1. I thought these lamps were produced up till 2019? Why are people selling ballasts from 1970? I presume they should have also been produced up till 2019+-?
2. On the first listing i see that i need to use capacitor between L and N and I'm guessing its not included in the listing?
3. On the second listing ballast no longer needs capacitor, but igniter instead? Igniter = capacitor?

 

Hi, not really sure on that, ballasts do tend to last longer than lamps, though. Some of the old magnetic lumps that were installed in the bases of lamp posts did 50+ years..!

The capacitor across the supply is for power factor correction. It's not essential for circuit operation, but using one will reduce the apparent power used. Not usually a problem in domestic situations, but it can make a big difference to power bills in commercial installations. I'm a perfectionist, so I always include one in anything I put together. It's unlikely a capacitor will come with the ballast, but I have a reasonable stock of them and I'm sure I could find one if you need one. The second listing will still need a capacitor, an ignitor isn't the same thing..!

This going to be an expensive project  So far the lamp it self was the cheapest part  I have ordered the second listing, can you comment or link a suitable capacitor 
P.S. even the BY22D socket is no where to be found... Only Ebay offers for 30-50eur 
Also iv noticed on the electrical drawings that L connects to the ballast - how important is it? What would happen if I connect it to N (thinking that ill just plug the assembly to electrical socket and there's 50% chance for L or N)?

Heh..! Welcome to the wonderful world of discharge lighting 

The capacitor I can probably supply, also a bayonet lampholder, got a box full of those..!

The polarity on an AC circuit isn't critical, although it's better from a safety point of view if the line (L) wire goes where it's indicated, just in case somebody touches something they shouldn't..! Here in the UK we have polarised plugs, of course, so it's automatically correct, assuming you wire the thing up properly..!

Would one of these sockets work? https://www.amazon.com/dp/B08L6TTM95  I'm not sure if there's a difference between B22 and BY22D

Here's a complete fixture including lamp https://www.ebay.com/itm/115982677093?

Some people have run sox lamps on electronic fluorescent ballasts.

Dang, i wish i could have found that full fixture earlier... Oh well... Iv red somewhere, that BY22D and B22 are different.
Rommie, how can we do the capacitor/lampholder exchange?   

B22d and BY22d refer to the cap on the lamp, not the lampholder. The BY version has a raised section between the two terminals on the base, this helps to prevent arcing between them due to the higher voltages present on ignition.

I'll send you a PM later this afternoon.

There are a bunch of drivers here: https://voorraad.dbl-verlichting.nl/collections/philips-sox-exc-evsa
And inductive ballasts (which have to be used with an ignitor) here: https://voorraad.dbl-verlichting.nl/collections/philips-sox-bsx-vsa
They also have the ceramic sockets, though of course quite pricey at 22 euro.

Generic chinese white bakelite B22 sockets are available and work well for my SOX 18 on my diy'd ballast/ignitor circuit. I don't know if the isolation will be enough for the 'real' ignitors, or whether the extra isolation was only needed in case of a lamp that was removed or went open circuit. Arcing would be quite bad in that case, but normally the lamp will clamp the voltage down to its ignition voltage.

Avoid the really cheap chinese plastic stuff.

If you can't find the proper driver or ballast, you can try it with a fluorescent lamp ballast, and a capacitor parallel to the lamp that you switch in/out of circuit with either a momentary switch, or with a fluorescent starter: https://youtu.be/1DfxKqt4CLY
You will have to find a ballast that delivers the correct current (not power!) to the tube, plus or minus 10% or something. When the current is correct, the correct voltage will follow from that.

He has all the required stuff now, the ballast and ignitor are on order and I'm sending the capacitor and lampholder over the weekend.

Personally, I'd avoid anything Chinese if at all possible.

While buying local is the best thing to do, the reality is that even if you buy local and pay the premium, at least 50% of the time you later find the exact same thing on Aliexpress, Amazon or any of the other chinese supply houses.
I bought mine local, it wasn't until later i saw the same thing in China. But at least bakelite and melamine are hard things to (...) up. Thermoplastic stuff can have wildly varying properties, melting points and especially flamability levels. Bakelite is always either completely safe, or completely broken, and won't burn  

Either way, glad that it's sorted. Always nice to preserve more of the old stuff for the future.