Installing lightbars on a house??

[firemedic10584]

So I've got a project from a customer that will be a first for me - he's wanting two Whelen lightbars installed on the roof of a small cabin / party house. Obviously we will need converters for this since the house is wired normally with 110/220. I've got a general idea of how I'm going to do it, but curious to know if any of you have done something similar and how you did it. Any tips or tricks for this kind of install?

 

[StEaLtH2]

What are the lightbars he has? That will influence the install in regards to power consumption/need..
Does he want these to be switched on from inside the cabin? Or just say to an outside outlet and plugged in when needed/party time!

 

[firemedic10584]

What are the lightbars he has? That will influence the install in regards to power consumption/need..
Does he want these to be switched on from inside the cabin? Or just say to an outside outlet and plugged in when needed/party time!

believe it's two Whelen liberties - he's just wanting to be able to flip a switch and turn them on basically when it's party time lol

 

[gtpts27]

believe it's two Whelen liberties - he's just wanting to be able to flip a switch and turn them on basically when it's party time lol

Would need to consult someone more knowledgeable than I am to ensure safety mechanisms in place but, If I was doing this, I'd run the main bar harness into a waterproof housing with a terminal inside. I'd then run a larger gauge waterproof power wire from the terminal block/waterproof housing to a 12V industrial power supply that was somewhere inside. I'd then place a switch along the wire that sent power from the house to the supply... so flipping the switch turned on the supply, which then sent power to the terminal block, which then powered the light bar harness. Would certainly want a fuse between the supply and terminal block and perhaps elsewhere (again consult someone more experienced to ensure safety).

Only concern with this setup is if for some reason it's a bad idea to have the bar directly connected to the supply while the supply is powering up and down (is power not clean enough for an led bar when supply starting up and shutting down? not sure...). You could install a second switch powering a relay between bar and supply to counteract that problem (if it is a problem) by powering the supply and then powering the relay once supply up (and reverse for turning off).

 

[firemedic10584]

Hmmm.. you make some good points. I knew for sure I’ll need a couple converters. I’ll have to research a little more.

 

[JazzDad]

Buffer it with a computer UPS?

 

[firemedic10584]

Buffer it with a computer UPS?

Not sure what ya mean?

 

[gtpts27]

Not sure what ya mean?

UPS= Uninterruptable? Power Supply. I believe- but am not certain- that he's suggesting it can provide immediate full power (via battery) to bar for brief moment it would take a regular power supply to kick-in... but how it would need to be setup I'm not sure as I don't know much about them.

I'm still not sure whether there's really an issue w just hooking bar up to regular power supply and not worrying about it. It only takes a very brief moment for an industrial supply to startup and it may not put out any power out in that period. Even if it does, it may not pose any danger to circuitry on led bar. Industrial supplies are, I believe, more or less the same thing as a computer power supply (different than a computer ups) and I'd assume if computers don't have a hardware issue then an led lightbar wouldn't either.

 

[Chiefs Chrysler Ñewport]

Buffer it with a computer UPS?

HMMMM that may be a interesting solution. Of course he could just use a old and crusty battery with various pieces of wire twisted together as needed. Damn the idea of a UPS may be a pretty good idea!

 

[Stampeed Valkyrie]

HMMMM that may be a interesting solution. Of course he could just use a old and crusty battery with various pieces of wire twisted together as needed. Damn the idea of a UPS may be a pretty good idea!

@JazzDad makes a valid point.
A UPS type setup would always provide power via 12V Battery. The 12V inverter would be used to recharge the battery while the bars are in operation.
This would do 2 things..
1 immediate clean power
2 no power surges or sags during operation.

Since the battery would always be providing power it would act as a buffer and it would always provide clean DC power.

 

[MtnMan]

The power supply turn-on/off shouldn't be a problem, and a UPS won't provide any benefit.

Start by determining the actual current draw of the lightbars, and get a DC power supply rated for the load plus 50% or so. Use appropriate size wiring, fused close to the source. If this is intended to be a permanent installation, the wiring should be UL listed (Class 2 low voltage) and compliant with any applicable codes. You can use watertight flex conduit for the final connection to the bars.

For more ideas, check out some resources on low-voltage wiring for residential and commercial LED lighting.