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Permalink Reply by christopher fryatt on August 7, 2017 at 1:11pm

using em on panel for lights and ads-b power, 5 in all, installed in 2009 1 failed at toggle , (broke off) 

expensive but space saving

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Permalink Reply by christopher fryatt on August 7, 2017 at 1:20pm

pix

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• buttons.jpg, 881 KB

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Permalink Reply by Gary Motley on August 7, 2017 at 8:24pm

I used about 10 of the switched circuit breakers on my Sonex for over 600 hours and they were trouble free. I am not using them in my CruZer because I need about 30 circuits and elected to use fuse blades in a remote area to save space.

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Permalink Reply by John Austin on August 7, 2017 at 8:30pm

I've used the W23 series (push-pull rather than toggle) as a switch for my MGL autopilot servos (which also automatically turns the autopilot off on my XTreme EFIS). Makes for a very compact installation and impossible to accidentally turn "off" since you have to grasp it and pull it.

John

N750A

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Permalink Reply by Bob Pustell on August 10, 2017 at 10:06am

I have switch circuit breakers in the panel of my 1947 Stinson 108-2. They were installed as part of a wiring moderniztion about 20 years ago and are still going strong, no failures or problems. I have only had one electrical failure that required a unit to cycle but cycle it did - when the strobe power pack shorted internally the strobe switch-circuit breaker handle turned itself off. I don't know the brand but they are aircraft specification units that look similar to the Tyco you show an image of.

By the way, standard "pop out" circuit breakers are not intended to be manually cycled on a frequent basis and using them as a switch will supposedly shorten their service life significantly. John mentioned using them as an off switch for his autopilot servos. If the intent is only to disable the servos in the event of an emergency that would work fine. If the plan is to turn the servos off with the pull type breakers on an "every time he flies" basis, that is asking for trouble. That is thirty year old information from a circuit breaker manufacturer but I expect it is still good info. If one wants to use a circuit breaker routinely as a switch it should be a switch-circuit breaker. If you want to avoid accidentally turning that unit off you could install a red safety cover over the switch handle to make it hard to cycle the switch handle of the switch circuit breaker by accident.

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Permalink Reply by John Austin on August 10, 2017 at 2:22pm

Bob,

I'm sure what you said about standard pop-out breakers is correct, but I didn't refer to a "standard" pop-out breaker ... I specified that I used a Tyco W23 push-pull breaker.  Tyco W23 circuit breakers are approved and designed by Tyco to be used as an On/Off switch and are rated to perform within spec for 10,000 mechanical On/Off switch cycles (and actually, that's 4,000 more cycles than they are rated for acting as a circuit breaker)! They are also approved by MGL as a switch to disable the autopilot. When the EFIS detects the power cut to the servos, it turns the autopilot off - it is quite clear in the installation manual it is an approved (and recommended) method.

You can get the exact same W23 with a toggle switch, if desired, but then you really should guard the switch if it controls a critical circuit to avoid accidentally turning it off - but like I said, a push-pull switch/breaker is impossible to accidentally turn off since you have to deliberately grasp the button and pull it out.

John

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Permalink Reply by Bob Pustell on August 18, 2017 at 7:13pm

Sorry, John. I misunderstood. Yes, a push pull breaker approved for manual on-off would be just fine. My bad!

Bob

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Permalink Reply by John Austin on August 20, 2017 at 7:18am

No apologies necessary - just wanted to make it clear there are circuit breaker switches available and appropriate for use as a switch.

John

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