28v lighting

[shaneb]

Hey guys,

Hoping someone can point me in the right direction.  I have two map lights out of a Lear 45 that is 28v.  Can I use these in my sim by connecting to a  AC /DC converter  24v dc power supply and use the switch that is already mounted on the light assembly . . it appears that the switch may also be dimmer.  Someone correct me if I am wrong . . electrical components is not my strong point.   Is it possible to use a lower voltage bulb?

[when acting as a wave]

Hi there

I thought I'd ask my father for you, and here was his reply (hope it helps):

From your photos, it appears to be just a rheostat (high power potentiometer) and a lamp.

You can run it off 28 volts AC from a small mains transformer if you wish. (24 volts AC will work virtually the same)  It does NOT need to be DC.
Just make sure you use a transformer that can readily handle the current each map light can consume at max brightness. (ie Watts = Volts X Amps)

If you use a lower voltage lamp, and use a lower voltage power supply, the dimming action will not be the same, but it will work fine. The resitance of the rheostat is matched to the current rating of the lamp that is fitted.

Dean.

[shaneb]

Hi Dean,

Thanks for the info . . I was hoping I would be able to use the lights without changing out the switch . . so that is some good news. 

[Boeing Skunk Works]

You might want to be sure that it's not a 400Hz rheostat. If I remember correctly, the Lear uses 400Hz AC. If you apply 60Hz power to your rheostat, it's likely to burn up. If the aircraft power is ran through an inverter to 60Hz, no problem.

[shaneb]

You might want to be sure that it's not a 400Hz rheostat. If I remember correctly, the Lear uses 400Hz AC. If you apply 60Hz power to your rheostat, it's likely to burn up. If the aircraft power is ran through an inverter to 60Hz, no problem.

Is there a way to visually tell if the rheostat is 400Hz?   

[Boeing Skunk Works]

Only if it's marked. If it has a part number on it, you might find it on the manufacturers web site.

[jackpilot]

My 2 pennies 4 what it's worth:

Put a 12v car bulb and reostat behind the knob, et voila.

[shaneb]

Thanks guys for the info . . greatly appreciated!