[Amps] SCR to adjust 240v to 200v

[Jim Brown]

Not quite. What is needed is a boost-buck transformer to go in 
series/parallel with the primary of the big transformer in the PSU.  
Primary of the boost/buck goes across the 240V line, secondary goes in 
series with the primary of the big transformer, wired out of polarity 
(that is, so that it subtracts 40V from the 240V). What you're looking 
for is a boost-buck transformer rated for 240V and a turns ratio of 
240:40 stepdown. The secondary must be rated for at least the current 
drawn by the Henry PSU.

Boost-buck transformers are not expensive compared to other big 
transformers because they're handling much less than the full power of 
the load they're used with. I see them at hamfests/swapmeets. They 
usually have multiple taps on their secondary so that they can 
accomplish different voltage shifts.

73, Jim K9YC

The On Fri,8/12/2016 12:00 PM, Ron Youvan wrote:
>   I would measure the incoming line Voltage RMS then I would locate a
> used 240 Volt to (normal Voltage - 200) Volt transformer and buck the:
> 240 - 200 = 40 Volts at enough Amps with it.
>   SCRs are headaches just waiting for you.