New member with mainly a safety question

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bil

Member
Location
dallas tx
....but I hope to learn a few other things as well.
I replaced a ballast kit in a 150W HPS lamp. It is an antique barn light housing.

I went to supply house and got Advance 71A8912 (HX-HPF). That was the only one they had for s55. I wired it up according to the best of my abilities.

Now, I put 120v to it and it lit. As this was my first time to deal with any HID, I sat back and watched. Here are my observations: First the ballast gets hot, 200F (90C) hot. Second, amp reading at supply was 1.5a or so, and this was within specs (I think) However, it was pulling twice the amps between the transformer and lamp, 3.2a.

Again, this was my first HID wiring. I followed the diagram and clearly marked wires, but still there was a doubt in my mind. Specifically the use of 2 "commons" and the capacitor in series on the common side.

So, the most pressing issue is temperature of the ballast. As far as I can tell from asking around is that this is normal. Please enlighten me.

I wish I could post a pic of the wiring diagram.
 
kwired

kwired

Electron manager
Location
NE Nebraska
The ballast is nothing more than a transformer - usually an autotransformer meaning one side of the primary coil is connected to one side of the secondary coil. The secondary voltage needs to match what is needed by the lamp regardless of what the primary voltage is.

So using some basic electricity rules if the secondary voltage is lower than the primary voltage then the current will be higher on the secondary than on the primary. The opposite is true if the secondary voltage is higher than the primary voltage. The difference in current will be proportional to the difference in voltage. Total volt amps of the primary will be same as the secondary, with only a slight difference for any inefficiencies.
 
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broadgage

Senior Member
Location
London, England
The higher current in the lamp leads is normal and no grounds for concern.

The ballast temperature is probably just acceptable but is hotter than I would like.
Is the fixture designed for this lamp and ballast ? or is it a possibly DIY retrofit in a fixture intended for incandescent lamps.
If the new ballast fails unduly quickly I see if the ventilation can be improved, or if a remote ballast kit can be installed away from the heat of the lamp.
 
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bil

Member
Location
dallas tx
Is the fixture designed for this lamp and ballast ?

Yes. I think it has always been HID of some sort. It is heavy duty looking and had the mogul socket. It might have been modified at some point from incandescent if that sounds probable to you. I dont know what flood lamps 40 or so years ago used. I found it as CW ballasted high pressure sodium. The ballast had a place above the lamp. ...Now here is where I may have broken the rules: The supply store did not have the same CW ballast. They sold me the high power factor type which did not fit. While wiring it up I read that this ballast (ignitor) cannot be moved more than 2 feet. I moved it 5 feet, plus the pigtails of 18 inch or so.

The supply store guy is an acquaintance who I did not want to bother, so I just found a vented box for the ballast kit and moved on. We will see ( or those with experience can tell me) what will happen. I could shorten that 5+ feet some, but this is a decorative situation so I will wait and plan to find an exposed box.

I checked on it yesterday and the cap. is buzzing like an alarm. It is plastic case type. I usually see metal cases for this rating - 14mf.
 
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bil

Member
Location
dallas tx
I mean near this rating 14 mf

I mean near this rating 14 mf

15mf 370 is metal case.
Can't say that I seen a 14mf until now
 
kwired

kwired

Electron manager
Location
NE Nebraska
Make sure you have right capacitor. Motor capacitors do not have as low of tolerance range with their ratings as ones intended for HID fixtures. HID's are much more sensitive to needing the right capacitance to work properly.
 
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bil

Member
Location
dallas tx
did not know that, thanks

did not know that, thanks

I am not sure what you mean "as low a tolerance" but I will just trust you

I was thinking about putting a much larger run cap in there just to experiment.

the buzzing cap just needed to be secured better...
 
kwired

kwired

Electron manager
Location
NE Nebraska
bil said:
I am not sure what you mean "as low a tolerance" but I will just trust you

I was thinking about putting a much larger run cap in there just to experiment.

the buzzing cap just needed to be secured better...
Click to expand...

Motor capacitors can be within 10 percent of the marked rating and that is acceptable. HID lighting will not work if 10 percent off. They have a narrower tolerance range.
 
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bil

Member
Location
dallas tx
okay that makes sense now

okay that makes sense now

I easily confuse myself

what do you know about the ignitor being more than 2 feet from the lamp
will the ignitor give out or the bulb or worse?

the handbook said larger wire was not the fix, but maybe there is dog-trick like coil the cable around length of wood dowel...or wear a tin foil hat or something
 
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Swamp_Sparky

Member
Location
Austin, TX, USA
If it's just a simple 150w HPS barn light, you might have been better off just replacing the entire fixture with a new one - Cooper, RAB, or any other number of manufacturers make suitable fixtures.

That being said, since you've already purchased a new ballast kit that didn't fit in the housing, what does that tell you about said ballast kit? ( Hint: it's the wrong one.) You can jerry rig it all day long if you want, but that ballast at 90c is too hot. Something is either mis-wired or it's simply a bad unit - it happens. Barn lights are fairly small housings, as HID lighting goes. Find the proper retrofit kit and install it exactly as the spec sheet inside says. Ilco, Halco, Howard, GE, and several others make kits for just about anything.

Just remember - there are some things you repair, some things you retrofit, and some things you just throw away and install new. A nice 150w MH LWP fixture would give you more usable and better light than that poorly working HPS. Just my 2?.

P.S. With regards to remote ballasting, the last place I worked had several 1500w MH fixtures in a huge warehouse remote ballasted as far as 500' away, and worked just fine.
 
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bil

Member
Location
dallas tx
Thanks

Thanks

I could have explained the situation better.
The lamp is a decorative type thing, or antique. It is a "barn light" because it came from a barn. Looks like a street light, basically. It is quite large. It is now indoors. Room size 40x 30 ft. The orange color reflected off the ceiling is desired.

According to my readin of the handbook referenced in this thread, this ballast is supposed to run that hot. Now, maybe I am mistaken. Please let me know if you suspect mis-wiring or ballast kit not matching the bulb, or something else

Yes there are remote ballasted starters available, but that was not my question.
I was asking what will be the problem with adding 5 feet to a starter that is listed for use 2 feet from lamp. I could probably cut it down to 3 or 4 feet.
 
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broadgage

Senior Member
Location
London, England
If the starter or ignitor is installed too far away from an HID lamp, then the high voltage starting pulse is partialy disipated by the capacitance of the cables.

In theory the reduced voltage might not strike the lamp reliably or at all.
In practice they normally work fine unless the distance is grossly excessive, a pedant might argue that increasing the distance between lamp and starter beyond that stated by the supplier is a violation.
 
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Swamp_Sparky

Member
Location
Austin, TX, USA
Post a photo with some dimensions if possible - might help in spec'ing something appropriate to retrofit it with. Also, when you're taking that antique fixture and upgrading/retrofitting it, remember to replace the lamp leads as well - they tend to get "crispy" over time. Also check the mogul base to ensure that it's pulse-rated, if not, buy a new one. Your local electrical supply house should have them, and depending on who they are, they may sell retail to you.
 
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