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Re: 12amp vs 20amp generator
Posted: Mon Dec 30, 2013 7:38 pm
by cessna170bdriver
gahorn wrote:...Landing/taxi lights are intermittent loads by definition, so the mfr'r only installed the generator to provide 80% of the continuous load (of the original equipment list....
Being the nitpicker I am: The generator should be capable of supplying 125% of the continuous load. In other words, the maximum continuous load should not exeeed 80% of the generator's maximum rated current.

Re: 12amp vs 20amp generator
Posted: Mon Jan 06, 2014 4:44 pm
by GAHorn
cessna170bdriver wrote:gahorn wrote:...Landing/taxi lights are intermittent loads by definition, so the mfr'r only installed the generator to provide 80% of the continuous load (of the original equipment list....
Being the nitpicker I am: The generator should be capable of supplying 125% of the continuous load. In other words, the maximum continuous load should not exeeed 80% of the generator's maximum rated current.

Thanks, Miles. .. I knew what I was thinking, I just wrote it wrong. I meant to say that the generator supplied was sized to accommodate the 120% continuous load definition...i.e., continuous load shall not exceed 80% of generated capacity. (edited yet again to clarify 3/9/15)
n2582d wrote:..Could you show me a picture of where you find that? In every iteration of the wiring diagrams I have it shows #14 gauge. Probably alright for the the later ones which have one 14 ga. to each light but too small for a continuous load with one wire going to two lights like in the earlier 170 serial numbers.
SN 26996.jpg
SN 26996 and Up.jpg
SN 26996 and on #2.jpg
Well, if that don't beat all! Gary, I see what you're saying, and my electronic copy of the IPC agrees. Once again, I'm not at home and cannot access the document I used to make my previous post and I'll have to wait until I return home to figure out where I resourced that info, but as I recall I used the actual part number for the wiring and found it to be 10 ga wire.
The GE4509 lamp is a 100 watt device, and rated at 14V, which equates to 7 amps. Mil-W-22759/16 wire in 14 ga. is rated to carry 7 amps continuously, so that should still be fine for continuous duty for the lamp. (But I'm danged disturbed that the IPC version you posted and I have in my laptop differs from what I resourced at home and now intend to get to the bottom of it as to why. I'll get back on this.)