Jewel Light Bar - New Ballast Help With Wiring Please

[bodge99]

Hello.

Are your lights similar to http/www.fishforums.net/index.php?/topic/265546-fixing-juwel-light-bar/ ?

I assume that you have seen this thread..

If you have had to cut a hole in the lighting unit to access the old ballast then is it possible that there are in fact two wires leaving the tube sockets.. they may be both connected to a third wire... is this the one you are seeing??

Is it possible to remove the tube sockets from the fixture?? It would appear that they are clipped in.

If you can do so, remove one and see exactly what is what. See if it is possible to open the socket (it may not be, it might be permanently sealed.) I'm guessing that the wiring connections are either behind a (clip on?) cover or are in the socket base.

If you do find a connection (looped etc.) then I recommend that you cut the loop and extend/replace the wiring to allow 2 wires per socket.

** If ** you can this, then you'll then be able to wire the lights as per the ballast wiring diagram.

If you cannot do this then you have a few options

Just wire in the ballast as before and hope! (I don't recommend this!)

Look for a ballast that will work in "2 wire mode".

Replace the tube sockets and wire the new ballast as per its wiring diagram.

If you want to try the first, then could you supply the part number of the new ballast. I've got access to *some* data sheets... I'll have a look and see what I can find...

If you decide to do the third, then this will solve any future problems.. the wiring would now be "standard" and you could then replace your ballast at any time with any standard electronic type in the future.

Could you also confirm the tube size and rating.. This will help me in searching for further options..

See http/cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=160946949022&clk_rvr_id=434979867578 for tube sockets that might be suitable.

Bodge99

 

[fish+peace]

Hey Bodge, there's alot to digest there but bear wih me i appreciate your helping me!

Firstly here's the model of the ballast i have - Osram QT-Fit8 2 x36

and here is a data sheet i've just found by googling it

http/www.osram.com/media/resource/hires/336477/Family-data-sheet-QT-FIT8.pdf

i see no mention of '2 wire' mode and as per data sheet it looks as though this requires wiring as per diagram on ballast only (no big suprise in hindsight)

SO as you've stated it looks as though i would have to have sockets with 2 wires per socket totalling 8 and then 2 of these 'commoned' as per diagram (23,24)

the original ballast was a vossloh schwabe elxe 238.527 if you look at the top of my post you can see the wiring diagram on that 1

So am i right in thinking that this old one didn't support monitoring which kills the power to a dodgy tube before it buggers the ballast whereas the new one does and therfore needs 6 wires.

if this isn't the case i maybe lost on a tangent somewhere lol...

incidentally the tubes are 30" t8's 25w

i have had the tubes holders off as they do unclip and they definately only have the 1 wire from each

 

[bodge99]

Hello fish+peace,

Spot-on.. You've got it right! This ballast has a decent level of protection under fault conditions..

Don't worry, it is a lot to take in at one go.. Just remember, no one is born knowing this stuff.

As with fish keeping in general, most people have to learn the hard way!

You have a good quality ballast now. I would say that it is far superior to your old one. BTW, how did the old one fail??

You are correct, this one will not support 2 wire mode. The second line in the Product Description "Lamp start with optimized filament preheating within 2 sec." gives this away.... This is referring to the tube heaters.

You now need to convert your tube sockets to 2 wires per socket if you are going to use this ballast.

Can you provide a piccy or two of your tube sockets (various angles, especially where the wire enters the socket)?

This might help in deciding how to proceed from here.

BTW, you will find different people referring to ballasts, tubes et. al. with differing terminology. As long as everyone understands exactly what is referring to what then problems and misunderstandings are minimised.

We **WILL** get this sorted!!

Bodge99.

 

[bodge99]

Hello,

I've been giving the tube socket problem some more thought...

Assuming that you cannot open the existing sockets or access the pin connections.

Possible solutions:

Obtain similar clip in replacements. One possible See: http/www.ebay.co.uk/itm/Waterproof-T8-BULB-BASE-SOCKET-DIY-LIGHTING-SPARE-PART-/160946949022?pt=LH_DefaultDomain_0&hash=item25792f8b9e .
Unless we can find something closer, then this might be the best/easiest solution

Use the sockets from a scrud Juwel unit (assuming that these are wired with 2 wires per socket). Most will be.

EDIT: The forum software changes the word "s c r a p" to "scrud"... guess why?

Advantages: You know that they will fit. Moisture isolation is as per your existing sockets.
Disadvantages: Sockets in unknown condition.. You would almost certainly have no problems, but the condition of the replacements is not certain.

Modify the existing tube connection method to use something like this: http/www.aquaworld.ie/56,555,waterproof-tube-socket-t8-26mm-1m . These are prewired. You would have to abandon the Juwel sockets and use screw on tube clips to support the tubes. See http/www.ebay.co.uk/itm/10x-T8-Fluorescent-Tube-Holders-1-Terry-Clips-25mm-Clip-on-Tools-Other-Uses-/360545680051?pt=UK_Light_Fittings&hash=item53f2327ab3

Advantages: Easy to fix. Sockets are waterproof/splash proof.
Disadvantages: The end result does not look as good as the Juwel solution. You would have to seal the holes where the original tube sockets clip in. Sealing bungs are available in various sizes.

I've used this type to solve a problem in an Aqua One UFO 750 bow front tank. The tubes used in these are of a non-standard length (read this as "more expensive tubes"). The cheapest and quickest solution was to use the above type sockets and tube clips in conjunction with standard size tubes. But I digress!

Modify the existing sockets to take new innards.. I've done something similar with a vintage lab UV steriliser. The tube sockets in this one were made of "Unobtainium"... A design that I have never seen before.

Disadvantages: Requires DIY skills and a lot of patience.

Whatever you do **please** don't just use standard (non waterproof) clip in sockets. The whole installation has to be moisture proof. There is an electric shock risk otherwise.

I'll keep looking.. I do like finding cheap(er) solutions to potentially expensive problems!

Any luck getting pictures?

Bodge99

 

[bodge99]

Hello again,

I've just read your last post again and have noticed something.

Regarding your ballast and your tube ratings..

You are using 2 x 25W tubes with a ballast rated for 2 x 36W. There is something here that you should be aware of.

The ballast is designed to supply a fixed maximum current through the tubes under working conditions. The longer the physical length of tube that is used, the higher the voltage that is required to be applied across the tube.. This tallies with observation.. the higher the power required, the longer the tube needs to be (Yes, there **are** exceptions!).

In your case, the ballast is "expecting" to see 2 x 36W tubes and will attempt to generate its operating voltage and maximum tube current to suit.

As you are using 2 x 25W tubes then there is obviously some sort of "mismatch".

O.K. How does this affect you..?

As usual, the exact consequences depend on the design of the ballast. It all depends on how much "leeway" has been allowed in the design. You could only predict this **exactly** by conversing with the ballast design people... Somewhat difficult!

What I would expect to happen is one of two things...

Either:

As this is a "better than some" ballast design, the monitoring/control electronics will cope perfectly O.K. even though the tubes used are out of specification for the ballast.

Or:

The tube will be overdriven slightly.. This will reduce the life of the tube by a small amount..

You would appear to have two options here..

Obtain a matched ballast or just carry on with what you have got.
Given the amount of aggro you have had so far with this one, I would be not be surprised if you do the latter.

Just something to be aware of...

I'm got some stuff written down regarding some experiments I did a couple of years ago with some spare tubes and ballasts...
I'll see if I can find them..

More later.

Bodge99

 

[bodge99]

Hello, me again..

Wow! I did manage to find what I was looking for...

First. **WARNING** to anyone reading this. Unless you know exactly what you are doing the **PLEASE DON'T** try and duplicate the following. High voltages are used in fluorescent tube circuits.. **THESE CAN "REALLY" BITE** .

O.K. then.

I was experimenting with various ballasts and tubes to determine what effect that using incorrectly rated tubes had.
I was looking at the tube operating current and how this varied with different ballasts.

To keep things simple, no numbers here, just a description of what I found.

I used three types of ballast (7 makes in all). Two standard magnetic ballasts, one cold cathode type (the proper name for "two wire mode"). Also looked at was 5 electronic ballasts, 3 were unbranded and the other two were Philips and Osram.

I used two tubes.. a 25W and a 35W T8.

What I found was this:

Magnetic ballasts (35W): The current flow in the 25W was higher than with the 35W tube (by about 8%). Therefore the 25W tube was being overdriven. The ballast was also running slightly hotter.

Cold cathode ballast (38W): This one was horrible. It failed within a minute on the 25W tube. The measured tube current with a 25W tube was significantly higher than it should have been. Also RFI (radio frequency interference) figures were terrible.

Electronic ballasts:

The three unbranded ballasts returned similar results... The 25W tube had higher tube currents.. All results within 5 - 6% higher.

The results for the branded ones were the best.

The Philips ballast gave the best results. The 25W tube was still overrun slightly in both cases, but only by 3% for the Philips and 3.2% for the Osram .

Please note that this not a scientific examination of ballast technologies by any means.. I'm sad enough to enjoy playing with this stuff and I was just curious. I'm "into" electronics and vintage (valve) radio (as well as fish!) and there is a certain amount of "overlap" here. I was playing with recovered, old ballasts that were really best described as junk.

I don't claim that you can extrapolate these results to all ballasts... YMMV.

Just a general question to anyone reading this.. Is the information in this thread of any interest or use to anyone??

Bodge99.

 

[bodge99]

Hello,

Yet more info..

I've just found a datasheet for the original ballast. The illustration of the ballast is slightly different but I think it is reasonable to assume that the specifications are the same. This one is rated as 2 x 38W !

Bodge99

 

[bodge99]

Hello,

T8 and T5 waterproof tube sockets:

See http/www.covershield.co.uk/Lampholder.html

T5 is fifth down. T8 is ninth.

Bodge99.

 

[fish+peace]

Thanks Bodge i've email them for a pricing - sorry i've not given much back to this one lately - been a very busy time lately, i'm unclear how the wires to the tube sockets connect on my setup else i'd be tempted to just wire the extra wires into it. I assume on the generic ones like above there is a simple method of adding wires to the socket?

 

[bodge99]

Hello,

Don't worry about it... I know the feeling..

If you do go this route, then you'll probably find the the tube sockets have either screw or (more certain) spring loaded "push in" connectors...

You should find that your existing wiring is solid core..

Normally, something like 0.5 - 1.0 mm Sq. cross sectional area wire is used.
In a pinch I've used 1mm lighting cable (**MUST** be solid core) on my lights... The stuff used for household lighting circuits.

See http/www.ebay.co.uk/itm/3-Core-and-Earth-1mm-Cable-6243Y-10-Metres-/170971212027?pt=UK_BOI_Electrical_Components_Supplies_ET&hash=item27ceada8fb

You can get this stuff in 2, 3, 5, 6 or 8 core + earth. Most DIY or electrical wholesalers sell it by the meter... Just get whatever is the best value for money.. I would remove the outer insulation and use the conductors in pairs... Obviously the bare earth wire isn't used for tube connections.

Keep each socket wire the same length (as a pair). Each socket wire pair can have different lengths, but aim to have matched pair lengths per socket. (Yes there **IS** a reason for this...).

If you need a tip on how to remove the outer insulation (sheath) easily then just ask..

It's possible that your existing sockets are manufactured as "sealed for life". You could just cut the wires...

This would mean you adding to the existing wiring, but it might be better to replace with new wire. You could then keep the old tube sockets intact with their wiring for the day when you want to use them on another tank and have access to a cold cathode ballast...

More when required ;>)

Bodge99

 

[fish+peace]

got a price back from Covershield on the tube holder

T8IP65 T8 Waterproof lamp holder is £2.80 each x (4) = £11.20
UK Carriage £4.50
20% Vat £3.14
Total £18.84

if i cant connect the existing ones easily then i'll probably do a quick price whip round and buy them if its a fair price - thanks for the tips

 

[fish+peace]

Well to revive an old thread, i bought 2 x new tubes as mine were due to be changed (t8 juwel day glo and warm) and when i swapped them over to my hacked juwel light canopy they flickered for a second as though they were starting and then nothing.. i put it an old tube and a new one and it worked, put in 2 new ones and nothing so i've come to the conclusion that as per bodgers sugestion my wiring was just limping along.
 
I could buy some new waterproof tube holders with 2 wires at around £20 or i could buy an external dual arcadia at around £40 but with the wries etc and messing i thought sod it and have bought a new t5 juwel lid for £84

 

[Tracycx8]

Thanks for your comments, they were very helpfull, I had exactly the same problem, I got a new ballast and re wired the existing tube holders, problem solved, all for the cost of £10, thank you