Circuit Breaker Sizing

SoCal 182 Driver

SoCal 182 Driver

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SoCal 182 Driver
Friends - I'm having wingtip strobes installed in my 14v Cessna 182. The specs indicate that the maximum draw for the pair is 9.8 amps. What size circuit breaker should be used?

I'd appreciate any advice you can provide.

Thanks!
 
The circuit breaker is there to protect the wire, and it shouldn't be loaded to more than 80% of nameplate rating.
In your case, based on standard breaker values, it looks like you'll need a 15A breaker.
And because of that, your minimum wire gauge should be 16. Or larger, if the voltage drop is more than 0.5V.
For reference, anything more than 10 ft will generate a voltage drop higher than 0.5V at 10A. So you'll probably need 14 or 12 AWG wire.
 
AV8R_87 said:
The circuit breaker is there to protect the wire, and it shouldn't be loaded to more than 80% of nameplate rating.
In your case, based on standard breaker values, it looks like you'll need a 15A breaker.
And because of that, your minimum wire gauge should be 16. Or larger, if the voltage drop is more than 0.5V.
For reference, anything more than 10 ft will generate a voltage drop higher than 0.5V at 10A. So you'll probably need 14 or 12 AWG wire.
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Very helpful. Thank you.
 
SoCal 182 Driver said:
What size circuit breaker should be used?
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AC 43.13-1B gives guidance on sizing CBs in Chapter 11. The strobe installation info should address wire size which should give you a starting point. However, you may also want to ensure the recommended wire size is appropriate for the wire lengths for your specific install which are also given in Chap 11.
 
Bell206 said:
AC 43.13-1B gives guidance on sizing CBs in Chapter 11. The strobe installation info should address wire size which should give you a starting point. However, you may also want to ensure the recommended wire size is appropriate for the wire lengths for your specific install which are also given in Chap 11.
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Thank you, as always!!
 
Review the STC drawings and installation instructions. Some LED strobes give separate figures for peak and average draw, and specify a wire and breaker size that may be less than the peak.

10 amps sounds like overkill. I've got my WATs on a 5A breaker.
 
Ed Haywood said:
Review the STC drawings and installation instructions. Some LED strobes give separate figures for peak and average draw, and specify a wire and breaker size that may be less than the peak.

10 amps sounds like overkill. I've got my WATs on a 5A breaker.
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The installation manual is sparse, at best! The STC is silent on this issue. :confused:
 
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SoCal 182 Driver said:
The installation manual is sparse, at best! :confused:
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Are you installing the part under an STC? If so, there should be an FAA approved document with installation specifications. It could be separate from the product manual. Check the support section on the product website.
 
SoCal 182 Driver said:
AeroLEDs 650 Pulsar. STC # SA04837NY
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Are you replacing only the light assy's and using the existing wires? If so, once you properly remove and bypass the original power supply, then the existing wires and CB can be acceptable. If you're also replacing the wires, then you have options. The Instructions allow for both and use AC 43.13-1B as the basis which is common SOP.
 
Bell206 said:
Are you replacing only the light assy's and using the existing wires? If so, once you properly remove and bypass the original power supply, then the existing wires and CB can be acceptable. If you're also replacing the wires, then you have options. The Instructions allow for both and use AC 43.13-1B as the basis which is common SOP.
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I'm making some assumptions here, since my A&P will be doing the work and making the decisions...

My understanding is that the existing Nav light wire (with its circuit breaker) will be retained, and used for the Nav light portion of the new AeroLED units. Two new wires will be run in each wing...one for the strobe, and one for the strobe sync wire. A new circuit breaker will be installed for the strobes.

The current Nav lights are factory incandescent bulbs, so I'm assuming there's no power supply between the light and the circuit breaker.
 
I'd probably run no less than a 5A circuit breaker for that duty cycle. Maybe 7.5A.
Wires will still have to be sized for no more than 0.5V drop at peak current.
 
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