[Collins] 516F-2 wiring

[Dr. Gerald N. Johnson]

On Tue, 2007-12-04 at 08:15 -0500, David Knepper wrote:
> Dr. Jerry, I have seen both fuses in the primary leads and a double throw 
> single throw switch in both lines.  Is that the "best" solution.
> 
> Thanks
> 
> Dave, W3ST - W3CRA
> Collins Radio Association
> www.collinsra.com
> Join the largest Collins group in the world
> Nets on 7208 at 4:30 EDST every day and
> Monday at 3805 at 8 PM EDST
> 
That is British practice, but since one fuse and a single pole switch is
less expensive, the American standard is to put switch and fuse in the
hot side only. In British practice, neutral may not be near ground
potential either. American practice forces neutral to be grounded at the
main panel and uses the ground wire as the conductor to intercept the
shorts to case that could otherwise return to earth through a user
causing irreparable damage to the user. US NEC and OSHA believe in
grounds and grounded neutrals so accept the single fuse and switch.
British puts fuses in the plug cap, customized to the load and cord cord
conductor size, doesn't believe a 20 amp branch breaker protects 18
gauge zip cord as we do. Though its getting hard to find 18 gauge
zipcord these days, the smallest extension cords are 16 gauge.
-- 
73, Jerry, K0CQ, Technical Advisor to the CRA
All content copyright Dr. Gerald N. Johnson, electrical engineer