In a message dated 97-12-02 04:35:26 EST, ddjones@nas.com writes:
> In responding to the querry about what type of coax to use, KC5UOO
> suggested running 110 Vac to the top of a tower to operate an antenna
> switch. Please note that this is potentially LETHAL unless industrial
> grade installation guidelines are used throughout the project. That
> means running metal-type conduit up the tower for the AC power line.
>
> It is far safer to run 12 Volts ac or dc to the top of a tower to
> operate switches, so long as the relay coils are consistent with
> that voltage.
>
> Just a word of caution........Avoid running 110 Vac up to the top of
> a tower if at all possible, or if you EVER intend to climb that tower
> with the AC power on!!
I don't remember what the NEC says about this thpe of installation. I
think there is a 28 volt upper limit without the aforementioned conduit, etc.
That's probably why rotators run 28 volts or DC.
And don't forget the GFI at the bottom.
73, Steve K7LXC
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