130kW Coil Update

From: 	Greg Leyh[SMTP:lod-at-pacbell-dot-net]
Sent: 	Monday, December 08, 1997 5:13 AM
To: 	Tesla List
Subject: 	130kW Coil Update

We are in the home stretch at this point, now that the rotary gap
is installed and operating.  With the aerodynamic shrouding in
place, the 4 gap armatures still require approx 28HP at full speed!
The 30HP, 500VDC Westinghouse motor seems to have no problem with 
this, however.  Cursed aero drag = v^3!!  The SCR stack is holding
up as well, although an initial phase rotation error slammed the 
motor to half throttle from a dead stop once.  I was amazed at just 
how fast that motor could accelerate 200lbs of rotating aluminum!

Now that all of the equipment is in the vault, we are running the
interconnecting wires and busbars.  The mains on the Navy base run
a bit high -- around 500VAC.  Fortunately, the Railway Museum has an 
old 200A battery charger, with a 480V to 92V 3PH xfmr inside!  We plan
to use this as an autoxfmr, and buck the 500V mains down to 408V,
which is close enough to the 400V mains in NZ.

Abarring further contingencies, we should be doing the initial 
slow-pop measurements this wknd, with power ramp-up in the following 
few days.