Hello!  I'm having an issue with a fluorescent exit sign that I own.  It takes the small 6-watt bulbs, and is 120v AC unit.  It has two ballasts inside, and I have not managed to see what else.  The thing is layered like a cake on the inside, several rows of hardware.  lol   Anyways, when I plug it in, the "charge" light lights up, and I can hear the bulbs make "pinging" noises, but they never light.  If I push the "test" button, the ballasts will either do nothing, or sometimes they will change their tone to a loud humming noise. I thought it may have been burned-out bulbs, but even with new bulbs in, it still does the same thing.   Is there anything I can do and/or check?  I do have a little probe voltmeter, but I don't know how to use it.  I do not know if the unit has any starters in it, I have not gotten that far at dismantling it yet. If anyone ca help, thanks!

Those circuits have a relay that switch the lamp between the normal Switch Start (preheat) circuit, and the emergency Instant Start circuit

The relays are supposed to :

Break the starter loop (st the Instant Start ballast is not powering the starter instead)

Break the main Switch Start circuit (either between ballast and lamp, or lamp and neutral) so that the Instant Start ballast does not feed back the mains and does not get mains voltage into its output

I think the emergency module is miswired in a way that when normal working the Switch Start ballasts and starters are in the circuit but the lamps are not (bypassed etc), and when in emergency the Switch Start ballasts are connected between live and neutral directly

I hope that no damage happened by feeding mains voltage into the output of the Instant Start ballast

I will check again, and see if I wired it correct.  All I did was put a standard two-prong lamp cord on it.  The previous seller did too.  The previous seller had two of them the exact same, and one was burned-out, with burn marks on the inside.  Whether that is the same with this one, I have no clue.

EDIT:  I gave it a quick look, and the hot wire from the AC power is connected to one wire on the test switch, which is in turn connected to another wire, which is connected to one of the black wires from the right ballast.  The neutral wire is connected to a white wire which goes down somewhere in the lower part of the unit.  I'll post a photo here once I get a chance.   I wish I could be, but I am just not familiar with fluorescent fixtures, and do not know how they are supposed to be wired up.

The modules as i know them here. contain a step down transformer, the battery charger, some logic to switch the emergency on or off + transfer the lamp batween the circuits, and instant start ballast powered from the battery when the logic enables it

The test switch is supposed to be a normally closed switch which when pressed interrupts power to the emergency module to make it think there is power outage. In the ones we have here the switch is wired in the low voltage output of the transformer, but it can work the same if it is wired to the 120/240V input of the emergency module (before the transformer)



Fixtures can be miswired from the factory. I seen a 2x18W PL fixture (2 magnetic ballasts) that was miswired in a way that 1 lamp was connected directly to the mains and 1 with 2 ballasts in series. When powered, in 1 the starter exploded and filaments blew and 1 was flashing but unable to start

Try this :

Assemble the normal Switch Start circuit only and test it

Connect the emergency module and battery, nothing else connected to them, to mains to charge the battery and see if it's charged

Disconnect it from the mains completely by unplugging it (to simulate power outage, but also to not have any mains potential at all). Figure out (from the tracks on the board) which are the Instant Start ballast outputs (they go to the relays or output of HF transformer, sometimes there is capacitor in series with the transformer output). Connect the lamp to them for test (without the Switch Start circut). If unsure, poke the lamp wires directly to the solderings of the output of the HF transformer

You can usually hear the HF noise from it when it is working



When connected to mains power the entire low voltage circuit (including battery terminals) may be at mains voltage vs earth so be carefull when its plugged in. The Instant Start ballast when working from the battery only can shock too but it is less powerfull than mains - at least my experience

Perhaps it is my fault for accidentally posting this in the wrong category. (I have since moved this topic to the correct place.)  This is a unit from the 1960's or 1970's.  It has no computer circuitry in it or circuit boards.  Just good old fashioned buttons, wires, and transformers. I do not even believe it has a battery in it, but it has the option for one.

In any case, I found what might be the issue.  There's a hole in the ballast!  It's a hole big enough to stick a ballpoint pen tip into, and electricity has escaped and arced out, burning the paint on the inside of the unit.  Perhaps that is why the sign was retired.  lol

Also, there's a little label on the interior talking about an "emergency ballast".  Is that the reason for having two ballasts?

By the mid 80's there allready was proper HF technology

In the 70's there were simpler inverters which were not capable to go above medium frequency, but i can imagine some electronic "Medium Frequency" ballast which is similar to today's HF ballast built with 70's components

In the 60's there might be some very preliminay inverters, but it is possible that they used a mechanical device to convert DC to pulsed DC and feed that to a transformer. This device is basically a relay that disconnects itself so when powered it will buzz continuously. Then current from it (parallel to the relay coil) is going to a transformer

It is possible to run the fluorescent lamp on DC with the normal ballast and starter (just add resistor in series such as incandescent lamp). Is the voltage of the battery written somewhere ? If it is extremely high (few tens V) this might be the case

Another option is that they used the fluorescent lamp's electrodes as incandescents, or a separate incandescent lamp inside the same fixture

It is interesting to see actually how it is built and what circuit is used. Some more pics showing it all would be cool



If 1 ballast is a simple Switch Start (2 wires) and 1 is that "emergency ballast" (more wires), thats the answer

If both ballasts are Switch Start, There are few reasons why 2 ballasts can be used :

Reliability - when 1 lamp is EOL it does not affect the other, so suitable for emergency fixture

Availability of ballasts - maybe the manufacturer was out of 13W ballasts so he used 2x 6W ballasts instead (though i think it might work good enough with 2 lamps in series on 1 6W ballast)

Knowledge - it is possible to make emergency circuit with a Switch Start circuit with 2 lamps in series, but some manufacturers dont know that so they use separate ballast for the lamp thats connected to the emergency circuit


Is the balast with hole a Switch Start or that "emergency ballast" ?

Both ballasts are Robinson-brand and are identical twins.  Exactly the same.  That's all I know

Here's a pic of the unit on the outside:
http://www.lighting-gallery.net/gallery/displayimage.php?album=2185&pos=1&pid=62890

Will have to do a YouTube video upload of the unit, since attachment photos will not work.

EDIT:  I removed the bottom portion, and found a black wire that is disconnected that is leading to the emergency (3rd) ballast, which in turn leads to the battery (which highly resembles a pipe bomb) lol. The emergency ballast is a metal box, packed with a bunch of fuses and circuit box things.

***So, do I re-connect the disconnected hot (black) wire from the emergency ballast, to the hot (black) wire from the test switch, and then connect both of those hot (black) wires to the AC power cord?  Then just connect the white one to the neutral on the AC power cord?    

I know that I did not screw up this sign, as that burn mark was on the inside before I even touched it, so if the ballast that has a hole in it is fried, I'm going to have a (heck) of a time finding a replacement.  I will have a youtube upload up in a few hours, as it's about 10 minutes long and in 720p resolution.


EDIT 2: There are stickers on the emergency ballast and battery, which look like price tags, which list the MFG date for the parts.  This sign is from 1989, not the 1960's like me and the seller I bought it from thought.

EDIT 3: Included photo of diagram on how sign should be wired.  I can't read these kind of diagrams, so, if you could try to answer my question above, thanks!

EDIT 4:  Video uploaded - http://www.youtube.com/watch?v=A2zwQyGz3AQ

that Eballast can be a source of a problem, it a bit of a weird set up first i would check the two chokes on Ohm seting and see if you got continutiy it that pass then it the Eballast could be they relays not working right
or a PCB trace burn opened. and dont see any starters so i am asumming the relay take control.

you have one of 2 choices first one is converted it to conventenal preheat withwout the eballast
by taking that yellow and brown wires to a starter socket FS5 starter that one lamp
the other is same set up by taking the gray and blue wire to the starter socket
then you got a conventional preheater exit sign

two is taking to fix or replace the Eballast. most lighting shop carry them but it not cheap.
i would check the PCB traces for any burned out traces, check all caps, relay see if it sticking
and check the fuse too. lastly then the charging circuit. the orange wire should be capped off as for 277 volts
if you still want to keep the emergency function the easy way is do step one and hook it to a computer UPS.

Please read my posts.  The emergency ballast is not an issue, because it was never connected.  There is a black wire for it that is capped off, which leads to the main power board inside the emergency ballast. I think that hot wire is supposed to be connected to the test switch, and in turn those 2 black wires are then supposed to be connected to the hot wire of the power cord(?).  Because that seems to be the problem why pushing the test button does nothing, because it is not connected to the emergency ballast/charger for the battery pack at all.  The white wire I originally had hooked to the neutral on the AC power cord, it goes directly into the emer. ballast.  The 2nd black wire from the test switch, it's connected to the two normal ballasts, with a orange wire also tapped in, which also runs to the emergency ballast box.  The wiring diagram says the orange wire is 277 volts, and there is no other orange wire...so should I unhook and cap off the orange wire, and connect the previously disconnected black wire instead?

The ballast that has burned a hole in itself, is one of the main little Robinson ballasts.  

A-HA!   Success!   I have mended it!   All I did was replace the 227v orange wire that was hooked to the ballasts, with the black capped-off 120v wire, and left the orange wire capped off.  I also put a computer power cord on it, and grounded it to the ground screw.  The lights light up now!  One bulb does not light, and the other lights up, but flickers off and on. Better than it was before, where it did nothing at all.  It's a start, and at least I'm getting somewhere.

So, I assume I would need new ballasts now?  I can't seem to find any for sale on eBay where I can buy one at a time, only lots of 200 or 300.

It is kinda hard to tell, because the wires are all together in a ball and the video never shows all of them at once. Try to spread out the wires and take a picture from farther away, so that all of the wires are visible and spaced out enough that they can be traced



The emergency ballast appear to have a "capacitive divider" to extract the low voltage for the battery from the mains, as a cheap substitute to a transformer. Such device does mind which wire is hot and which is neutral

Assuming the neutral (white) is connected properly, we have to identify the hot wire. As written on the label this should be either black or orange. Since there is no other black wire, it is _likely_ that you are supposed to connect the black from the switch to the wire nut with wires from 2 ballasts and orange wire, and leave the black from the emergency ballast alone, but i am not sure. To tell for sure, give pics of the electronic ballast's circuit board from either side



It is likely that the black wire slipped from the wire nut (which was not properly tightened in the 1st place) and shorted to the side of the ballast, blowing the burn marks. You can confirm this by looking for burn / melted metal marks on the end of the black wire from the switch, and if its end was near the place of burn before you opened the fixture

If thats the case, it would mean that the ballast with the hole is likely to be ok and not damaged since the spark did not come from inside the ballast

In case the blown hole was from inside the ballast, it means that there is isolation breakdown condition inside it. The fixture metal is not connected to earth. If you plug it in and there is power getting to the damaged spot, the fixture can shock. Same if there is any loose wire inside it. Dont touch it if the ballast with the hole is connected, or replace the power cable with one with 3 prong plug, connect the green wire from the new cable to the screw labeled GROUND inside the fixture - this will make the fixture safe even if there is powered failed ballast inside it. Dont power it up at all when there are wires with exposed ends inside



You can test the Switch Start ballasts by connecting the ballast like this with standard 120V incandescent lamp of around 100W power :

Green from power cable to metal enclosure of ballast (use a screw and nut in 1 of the mounting slots, be sure that there is electrical contact between them and not through paint etc)

Black from power cable to wire 1 of ballast

Wire 2 of ballast to wire 1 of incandescent lamp

Wire 2 of incandescent lamp to white from power cable

If the lamp is lighting up dimmer than normal, ballast is ok. Otherwise it is bad

Use a 3-wire power cable for the test and plug it in a GFCI socket at least once. If the GFCI trips this mean that there is isolation breakdown inside so the ballast is bad



EDIT

Ok yay for you

The lamp that does not light may be connected to bad ballast, or the starter for it (simple glow starter, equivalent to Philips S2) is bad. The starters here are inside the emergency ballast and not replacable, but you can hack in a proper starter with socket

Use a 3-wire power cable for the test and plug it in a GFCI socket at least once. If the GFCI trips this mean that there is isolation breakdown inside so the ballast is bad

Problem is now solved, and I have done that.  GFCI did *not* trip, and both bulbs would light if I kept flicking the light switch off/on/off/on/off/on really quickly. 

Now when I push the test button, the indicator light turns off, and I hear a "clunk" noise like it is supposed to do, and the lights stop making ting noises (because it is trying to run off a dead battery with no power).  So that is a good sign, an it seems to be wired up as it should be now.  What a nightmare of a problem that was so simple!  lol

Thank you all for the help! 

That 2 lamps light if you flick the switch, mean that both ballasts are good. The problem is then with the starter that is inside the emergency ballast

See which one of the lamps is not starting. Lets assume thats the one connected to blue and grey wires from the emergency ballast. Disconnect those wires between ballast and lamp. Isolate the ballasy wires. Connect a Philips S2 / Osram ST151 / equivalent starter between the 2 wires from the lamp

That 2 lamps light if you flick the switch, mean that both ballasts are good. The problem is then with the starter that is inside the emergency ballast

No, I mean that they will light briefly, as in half a second, as I am flicking the switch off and on.  They will not light at all if I leave it run. They will remain off and make tinging noises.  Just one bulb flickers off and on in intervals of a half a minute or so, whilst the other bulb never lights at all.

Ok the Eballast inside that glass tipped bulb; that the starter, you can unsolder them and put in a new FS5 starter, that you have to take it out of the starter can. or get a starter socket and wire them in on the printed circuit board. to make it easier to replace in the future. but i think you can leave one lamp like Ash said on convention preheat setup
while one lamp can be on backup. That would be half the current draw AT least you got the hardest part working, now you just need let it plug in let the battery charged up. see if the inverter part fully works. that works with out the starter.
will go from there.