Connection marked as 'CA' on a fluorescent light


Hi Group,
I have a fluorescent light which has a dimming transformer in it and a four
pin plug. The usual 3 A,N,E and another marked as CA. which I'm guessing is
some kind of control line. What I want to do is to bypass the dimming
altogether and just use it 100%.
Can anyone give me some suggestions on where I might find some information
to do this.
I've tried a couple of Google search but have not really been able to find
out specifically what and how this 'CA' connection works.
Any help appreciated
Lorne...
Reply to
Lorne Bonnell
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"Lorne Bonnell" wrote
I have a fluorescent light which has a dimming transformer in it and a four pin plug. The usual 3 A,N,E and another marked as CA. which I'm guessing is some kind of control line. What I want to do is to bypass the dimming altogether and just use it 100%.
Can anyone give me some suggestions on where I might find some information to do this.
***CA stands for "controlled active". Connect it to the "A" terminal and wire the unit up normally. Make sure you use inch and a quarter Rapid Start tubes (the new krypton based tubes will not work in this circuit) and that the metal case cover is securely earthed to give a ground plane close to the tube.You may have to flick the on/off wall switch several times to get the unit to fire.The circuit is low power factor as there will be no power factor correction capacitor in the unit and it will draw almost double the current of a corrected unit.
Brian Goldsmith.
NB.There are some smaller diameter imported tubes on the market that are marked"Rapid Start",they are not and will not work in the RS circuit.
Reply to
Brian Goldsmith
Thanks Brian,
What sort of dolalrs are involved in the controler for these lights ? Would I be bettor of getting a controler as I have six of these lights to have fitted to my shed ? Is it somthing I could buy from L & H and just have a sparky wire up for me ?
Lorne...
Reply to
Lorne Bonnell
Some years back I saw a datasheet on a solid state dimming ballast, and it used a 10k pot that went from this pin to either neutral or active, and was used as a dimming control.
There is no guarantee that yours will be the same however, but when you look at it, there isnt really anywhere else that the extra wire can go to than active or neutral....

Reply to
KLR
If you want to save yourself a lot of trouble, and just have a light that works reliably, and will continue to work for many years (decades) then go to Haymans (or similar) trade counter, and buy 6 normal 50hz ballasts, (in the wattage to suit the tube) and wire them in place of these fancy dimming ones.
you may also need starter sockets/starters too (if the original was an electronic ballast without a starter) but they also sell them.
Here is a webpage that shows how a normal fluorescent light is wired internally follow example named "inductive single circuit"
(assuming you are competent to wire up mains circuits of course)
Reply to
KLR
"KLR" wrote
that works reliably, and will continue to work for many years (decades) then go to Haymans (or similar) trade counter, and buy 6 normal 50hz ballasts, (in the wattage to suit the tube) and wire them in place of these fancy dimming ones.
***** If as the OP wrote,the units are fitted with dimming transformers then the existing ballast will be exactly as you are telling the OP to go out and buy.The OP did not mention anything about "fancy" dimming ballasts.
****What a pity you are not competent to read the original posting.
Brian Goldsmith.
Reply to
Brian Goldsmith
Hi Brian,
In you opinion would I be better of 1. Doing as you suggested and using the active as the controlled active 2. Buying a controller (if this is an option, not to expensive > $100 ) 3. Fitting out the lights by removing the dimming trannie and fitting a starter etc,etc or what ever may be required using the existing ballasts
Weighing up the life of the lamps 6 fittings 2 lamps in each , cost of the controller, the mucking arround and costs of starters and holders
Thanks
Lorne...
Reply to
Lorne Bonnell
He didnt mention that they were fitted with a standard ballast, only a "dimming transformer" not a "dimming transformer in addition to the ballast". This implies only one "device" in there which (if there is one device) is going to be either a modern electronic dimming ballast, or a custom ballast/filament transformer in one package.
If there was also a standard ballast in there - Im sure he would have worked out what had to be done, or at least commented on it being there.
Either way, my advice will solve the problem for him & it will work with any standard tube on the market.
Over the years I have seen equipment from other countries with some very odd ballast/tube configurations. (especially from the USA) In most cases, I have found that its better to remove these odd setups from the start and put in the standard australian series ballast/starter system.
Thats life.
Reply to
KLR
"Lorne Bonnell" wrote> "Lorne Bonnell" wrote
Thanks Brian,
What sort of dolalrs are involved in the controler for these lights ? Would I be bettor of getting a controler as I have six of these lights to have fitted to my shed ? Is it somthing I could buy from L & H and just have a sparky wire up for me ?
Lorne...
****** Six by 36 Watts in a normal fluorescent dimming circuit using 40 Watt tubes and dimming transformers could be controlled by a "standard" 600 Watt incandescent lamp dimmer ,the rule of thumb for calulating dimmer watts is to multiply the total fluorescent loading in watts by 2.2 and calling this result,dimmer watts required.However you would need to provide a seperate,non dimmed (but switched) active for the dimming transformer otherwise the heaters (filaments) in the tubes will remain on and will consume some power even if the dimmer is at its lowest setting and the tube(s) light output is zero.Professional dimmers had a special "filament switch" that sensed their control line being at zero and switched off the heaters.It is generally agreed that dimming RS tubes in the standard RS circuit results in erratic performance below about 20% of light output as there is a VERY unstable loading on the dimmer.For improved low end stability you may have to include some extra "ballasting" across the dimmed line by the inclusion of a,say, an 40 Watt (or higher,consistent with stable behaviour)incandescent bulb.There are some dimmers which are "hard firing" and are much better performers when used with inductive loads such as fluorescent lighting,very little dimmed line "ballasting" is necessary.In any case,your fittings,while not being "old" are now rapidly being replaced by modern,high frequency systems that can use the modern krypton based tubes and do not require a power dimmer but can be controlled by a 0-10 Volt (or whatever) control line which is completely isolated from the mains.Alas,in your case,this does not appear to be so and you must make do with your existing setup. Yes,you could buy the bits from L&H or similiar but you may have some difficulty in finding the average "sparky" with enough knowledge to wire it up for you,especially in relation to the coprrect tubes to be used.Clipsal (and I think ,HPM) used to have a leaflet explaining most of the usual methods of dimming RS tubes using the Preheat dimming transformers.What ever you do,remember,death is so permanent.
Brian Goldsmith.
Reply to
Brian Goldsmith
I should had fessed this information up in the original post,
The light has two ballasts and a dimming transformer and two tubes, no starters. At the outset of this quetsion I had no idea that there was so manny configurations for flourescent lights.
Thanks
Lorne...
Reply to
Lorne Bonnell
There are many indeed.
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To make it work as a normal fluro, remove the dimming transformer, and install a starter on each tube.
Disregard my previous advice about buying ballasts, as there are ones in there already
Follow the diagram
formatting link
(top left example). to see how the starter is to be wired into circuit Note that this will be done for each tube.
Reply to
KLR
As I understand it, your fitting has what is commonly known as a "Filament transformer", and does not use a conventional starter. This type of set-up is only suitable for 38mm tubes. If you want to use the more common 25mm tubes, you will need to ditch the filament transfomer and use starters instead. That will also rule out dimming.
If you really want to dim them, most standard dimmers can be used with this type of load, however you need to check two issues. 1) The dimmer must be a "Leading Edge" type, that is suitable for inductive loads. A "Trailing edge" dimmer intended for electronic transformers will not work. 2) You need to derate the dimmer due because of the "reactive" property of the fluorescent ballast. So you should count each tube as effectively 100W. 12 tubes would require 1200W dimmer, which will cost over $200.
Apart from this, there is something else you should know. That is that fluorescent lamps actually don't dim very well with this type of 'Low-Tech" ballast. This is the technology of 20 years ago and has never performed terribly well. I think the only real advantage is has is that there is no starter needed, so a point of failure is elliminated.
My advice to you is to forget about dimming, and wire the CA to the A, as suggested in the first response. That advice assumes you don't mind to use 38mm lamps.
regards, Johnny.
Reply to
Johnny

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