# Lighting Inverter



## Southeast Power (Jan 18, 2009)

We have a project where the client is struggling to maintain a parking garage lighting system.
The parking garage has 300 T-5 HO strip fixtures in weather proof housings. 100 of the fixtures have an individual battery backup.
The client was contacted by an LED retrofit group and they found the foot candle requirements for the garage could be met with a product they rep.
They cannot supply a battery back up.
The total load, just under 5000 watts for the largest garage, could be supported by a lighting inverter.
Lithonia had some models that could support the load and provide the 90 minutes run time the AHJ requires.
The other solution would be a small generator which might be another maintenance problem for the client.
The generator option has been exhausted and is off the table.
.
Has anyone here installed lighting inverters for this type of project?


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## chicken steve (Mar 22, 2011)

Possibly Magnum makes what you're looking for Jrannis>

http://magnumenergy.com/wp-content/uploads/2012/08/64-0032-Rev-A-MS-PAE-Series.pdf

~CS~


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## Southeast Power (Jan 18, 2009)

Thanks Steve.
That was much more info than I could find about the big name, Lithonia.
Problem is the retrofit.
2/3 of the lighting is on time clocks and the balance of them, the battery backed up units, are on 24/7.
The loads are already segregated but I have to deal with the 3phase 120/208 circuits that feed them.
I'll have to find out if the neutrals are shared. 
That would not be an issue with a generator but might screw up the inverter output.
Best case would be to find that the EM was piped separate but, I suspect they might have, like I would have, just pulled an unswitched conductor and shared a neutral.


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## chicken steve (Mar 22, 2011)

Seems EM's might look a tad more economical there Jrannis.....~CS~


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## Southeast Power (Jan 18, 2009)

I think the heartburn they have is that changing those batteries at about $100 a pop plus labor, is never ending.
They have 1000 fixtures with 300 of them being battery back up.
The problem they had was when all of the batteries began their Swan Song ensemble.
They didn't forcast the expense and it destroyed the maintenance budget for a couple of years.
They know the cycle will repeat and want to mitigate the expense.
The LED conversion will more than pay for the entire cost with a very short ROI.

I need to specify and budget the equipment cost.
I could maybe get $8 or $10 grand into it without hurting the ROI.
I need to find a decent equipment distributor to help with that decision.


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## Electric_Light (Apr 6, 2010)

jrannis said:


> We have a project where the client is struggling to maintain a parking garage lighting system.
> The parking garage has 300 T-5 HO strip fixtures in weather proof housings. 100 of the fixtures have an individual battery backup.
> The client was contacted by an LED retrofit group and they found the foot candle requirements for the garage could be met with a product they rep.
> They cannot supply a battery back up.
> ...





jrannis said:


> The client was contacted by an LED retrofit group and they found the foot candle requirements for the garage could be met with a product they rep.They cannot supply a battery back up.


:laughing: :laughing: :laughing: Why would a lighting decoration firm call a garage operator other than to offer to redecorate the parking garage?

5,000 watt for 1 1/2 hours on battery? You'll need 7 1/2 kWh of usable capacity across entire temperature throughout the entire life of batteries. Do you have any idea how much batteries you need to do this? 

About a dozen of this. http://www.csb-battery.com/upfiles/dow01413876645.pdf @ like $200 a pop. 1,500 lbs of batteries and a battery room and those only last 3 to 5 years. Expect to budget about $600/year just for batteries, not including labor. A centralized inverter can let out the smoke and lose entire backup power suddenly, so you need a second unit for redundancy. :no: :no:

If any usable spaces are lost to make room for the battery room, you have to add loss of revenue to cost. 

As for the EM ballasts, you're looking at $100 x 100 = 10,000. and 8-9 years of service, you're looking at $1100-1200/year. Since they won't all fail at once and battery life is fairly predictable, much of it can be invested somewhere.


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## Southeast Power (Jan 18, 2009)

Electric_Light said:


> :laughing: :laughing: :laughing: Why would a lighting decoration firm call a garage operator other than to offer to redecorate the parking garage?
> 
> 5,000 watt for 1 1/2 hours on battery? You'll need 7 1/2 kWh of usable capacity across entire temperature throughout the entire life of batteries. Do you have any idea how much batteries you need to do this?
> 
> ...


The battery units in the fixtures have a very predictable life. It's short and, they are expensive to replace when all 300 of them drop dead iat the same time every few years.
kW is kW so, what's the difference if it's central or local. Central seems like easy maintenance to me.


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## Electric_Light (Apr 6, 2010)

jrannis said:


> The battery units in the fixtures have a very predictable life. It's short and, they are expensive to replace when all 300 of them drop dead iat the same time every few years.
> kW is kW so, what's the difference if it's central or local. Central seems like easy maintenance to me.


Short is relative. What are you expecting? 
Do you have the brand and model number? The Bodine ones use special high temperature NiCd and they're supposed to last 8-10 years and have a 5 year *warranty*. http://www.bodine.com/downloads/specs/B50.spec.(elc).L2300226.pdf

Emergency ballasts don't light up at full brightness nor do they need to. More important thing is spreading out over enough fixtures to avoid dark spots. Are they wired up correctly? It's less expensive when the life is predictable and failure is close together, but not all at once on the same day so you can replace them on a schedule all at once and ideally, schedule it together with lamp replacement if possible. 

This kind of coordinated maintenance requires something Light Emitting Decoration firms are not capable of planning. 

You need an unswitched hot if the fixtures are switched. If they were previously 24/7 and converted to swithed and the emergency fixtures are not getting the unswitched hot they need, I'm not surprised they're failing very quickly and that's a misapplication. 

UPS batteries are usually non-spillable standby lead acid batteries and the expected life is 3-5 years. Centralized offers no redundancy and inverters are problematic. If you want 7.5kWh of usable energy with a 5kW load, that's enough batteries to warranty a battery room requiring a permit.


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