[Boatanchors] AC inputs?

[Glenn Little WB4UIV]

Yes, some equipment is built this way. On a Navy ship, each leg of 120 VAC 
is isolated above ground. This is so that if there is an electrical 
causality where one side of the AC distribution becomes grounded due to 
flooding or some other mishap, the equipment continues to operate.

Be careful with those lighted fuse holders "the neat kind that light up 
when the fuse has blown!". When the fuse blows, the path to you is through 
the lamp. In the case of a 120 VAC indicator, the lens is clear and the 
bulb is probably a NE-2. The Navy outlawed these type fuse holders some 
years ago due to the shock hazard present when the fuse blew. The voltage 
is still there, just current limited.

73
Glenn
WB4UIV
USN(retired) ETCS(SS) 22 years submarines


At 05:33 PM 04/28/07, eugene at hertzmail.com wrote:
>Hi All,
>
>Picked up a TMC antenna multi-coupler.  It has a 3-pin mil connector
>that thanks to folks here, I have ordered the mating connector to make a
>cable. Question has to do with hot/neutral.
>
>So I was investigating how to wire this up and was trying to figure out
>which pin is hot and which is neutral.  Ground was easy to figure out.
>Far as I can tell, it shouldn't matter on this which is which, but I
>wanted to check with the experts.
>
>The two wires (hot and neutral) come in from the connector. Each passes
>through a fuse (the neat kind that light up when the fuse has blown!) so
>far, since both sides are fused, I think I'm ok. Then the fused sides go
>to a DPST on/off switch. So far so good.
>
>Then these switched wires go directly to the primary of the power
>transformer...So it seems to me that there is no specific hot and no
>specific neutral.
>
>Can anyone confirm that some equipment is build this way and that it
>might not matter?
>
>Thanks
>Eugene
>_______________________________________________
>Boatanchors mailing list
>Boatanchors at mailman.qth.net
>http://mailman.qth.net/mailman/listinfo/boatanchors
>** List Administrator - Duane Fischer, W8DBF/W9WZE **
>** For Assistance: dfischer at usol.com **
>$$ For vintage radio info, see the HCI web site $$
>http://www.w9wze.org