[AMRadio] 220 vac line

[Paul Christensen]

> Electric kitchen ranges with 3-wire plug run on 240V, with the neutral and
> ground bonded together.  So does the BC1-T broadcast transmitter in 
> original
> configuration.

And, so does the Alpha 70 and 77 series of HF amps -- along with some of the 
big Henry models.  In the case of each amp, neutral is used to run a 120VAC 
blower.  In the Alpha 70/77 they made it easy to separate neutral from 
chassis ground by cutting a jumper on the Cinch-Jones power plug.  The 
change doesn't even occur inside the amp.  I ran 4-wire, #8 AWG between the 
panel and the shack, terminating into a 30-amp twist-lock receptacle.  My 
only dilemma is that I have one receptacle and four amps, requiring a 
physical change of the power plug when changing between amps.  No really 
good solution comes to mind, mostly for convenience reasons.

At the time these devices were manufactured, it was acceptable to join the 
chassis to the neutral connection.  40+ years ago, the NEC may have strictly 
forbidden this practice, but the NEC is a premise wiring standard -- not a 
products wiring standard.  So, perhaps the root of this really goes back to 
what was allowed  under UL guidelines at the time.  Well after 1970, the 
manufacturers seem to have gotten the idea and had found a means to better 
utilize the blower between 120VAC and 240VAC service.

Paul, W9AC