Page 1 of 1

Correct Capacitor List

Posted: Thu Aug 20, 2015 3:05 pm
by Slyspark
Just wondering if anyone has a nice list / chart that shows the correct capacitor ratings for fluorescent / SOX / SON / Halide / MBF lamps on Magnetic ballasts as not all gear has the capacitor requirements sown on it. Would make a handy reference if anyone has one they'd be willing to upload?

Cheers :)

Re: Correct Capacitor List

Posted: Thu Aug 20, 2015 3:39 pm
by Tom
Off the top of my head caps are as follows; (Don't ask me how I remember, too many years with my head in the catalogues/inside fittings LOL) :rofl :doh
250v caps;
2uF = 4-13w T5, PL-S, 16w 2D
3-4uF = 18" 15w through to 4' 40w, 2D 28-38w, PL-L
5.5-6uF = 5' 58w/65w and 6' 70/75w, 50w MBF, 35-55w SOX? 4' 40w SRS?
8uF = 2' 40w, 5' 80w, 6' 85w, 80w MBF
8.4uF = 8' 100w ballast and starter switch. Upon switch-on, the starter closes and preheats the tube's cathode filaments. Upon opening, the magnetic field within the ballast collapses, causing a voltage pulse which strikes the tube. This is often repeated twice or more, causing the distinctive blinking at startup.">switchstart lagging, 5' 65w through 8' 85w SRS
10uF = 70w SON/MH, 125w MBF

440v;
5uF = 6' 70/75w lead
7.2uF = 8' 125w lead

Re: Correct Capacitor List

Posted: Thu Aug 20, 2015 3:51 pm
by Slyspark
Cheers!

Don't spose you have any ideas on 250w mercury at all?

Re: Correct Capacitor List

Posted: Thu Aug 20, 2015 11:09 pm
by Tom
13uF for the 250w MBF circuit. Take a look at the old Thorn catalogues we have posted in the gallery. Fully detailed gear and circuits sections are superb!

Re: Correct Capacitor List

Posted: Fri Aug 21, 2015 2:22 am
by Slyspark
Cheers Tom,

It's funny, but I had that idea earlier, spent ages trying to find the one I wanted, but did eventually find it and was able to light the fitting I wanted to. I meant to post here that I'd found it....

Might take some time to compile a list of all the capacitor sizes from there, I'd certainly find it usefull and I'm sure others might too. If I do do so, I'll post it on here somewhere. Old control gear always used to state the capacitor size on it, but none of the more modern stuff seems to any more - odd....

Re: Correct Capacitor List

Posted: Fri Aug 21, 2015 7:26 am
by LinearSLI-H
I have done lists on here for total HID/Fluorescent circuit watts and lumen figures, I could do one using the army of manufacturers catalogues I have, but it takes ages, and my other two lists are buried deep within the archives somewhere, which is not that readily accessible to find, but its easier to just ask for which one is needed like you did here :D

Re: Correct Capacitor List

Posted: Sun Sep 06, 2015 7:17 pm
by versalift09
Add to that list:
12uF for 100w SON
20uF for 150w SON
30uF for 250w SON
40uF for 400w SON

Re: Correct Capacitor List

Posted: Mon Sep 07, 2015 4:10 pm
by Paul
@Rich - are they in the forums somewhere or the gallery?
If you like I am more than happy to make them a PDF and put them in the technical reference area on the gallery....

Re: Correct Capacitor List

Posted: Mon Sep 07, 2015 4:49 pm
by LinearSLI-H
Yeah, their in the forums somewhere, if I remember their under lamps and not gear?

Re: Correct Capacitor List

Posted: Mon Sep 07, 2015 5:25 pm
by Paul
First PDF file.... Fluorescents

Re: Correct Capacitor List

Posted: Mon Sep 07, 2015 8:45 pm
by Slyspark
Ah, that's brilliant! I was going to make one, but that's perfect! Cheers!

Re: Correct Capacitor List

Posted: Mon Sep 07, 2015 9:54 pm
by Paul
Not a problem! I will be doing one for discharge too.

If you look at page 312 in the Thorn 1976 Catalogue, there is a table in there! :doh

Re: Correct Capacitor List

Posted: Thu Sep 10, 2015 11:32 am
by Paul
Here's one for discharge circuits....
@Davy... the value for 400w SON seems to be different to the one you have listed. Is this down to a different circuit or gear?

Re: Correct Capacitor List

Posted: Sun Aug 13, 2017 6:31 pm
by MissRiaElaine
Paul wrote:Here's one for discharge circuits....


I have 20μF listed for my 35W SOX lamp, data from this site.

Re: Correct Capacitor List

Posted: Wed Oct 04, 2017 5:42 pm
by MFL
Here is the list from Vossloh-Schwabe capacitors

Re: Correct Capacitor List

Posted: Wed Oct 04, 2017 6:03 pm
by Tom
I do find it quite interesting the huge contrasts in different capacitor ratings between lamps, even of the same wattage. We have 13-18uf caps for 250w mercury circuits yet the 250w SON needs 30uF! Old catalogues from the 50s, for say, a 4ft 40w ballast and starter switch. Upon switch-on, the starter closes and preheats the tube's cathode filaments. Upon opening, the magnetic field within the ballast collapses, causing a voltage pulse which strikes the tube. This is often repeated twice or more, causing the distinctive blinking at startup.">switchstart circuit list a 3.25uF cap yet an 18" 15w circuit was 4.5uF? Goes to show just how much ballast characteristics have changed over the years and indeed, how much they vary between manufacturers!