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Pacific Power 50 Hz Power Supply

The goal of this page is to give the status and capabilities of the Pacific Power 390-G AC Power Source for 50 Hz power to the IBM 1401 system.

at IBM

back side
at IBM




Pictures by Robert Garner & Ed Thelen

- Rated power to each of three phases, 6 KVA (over three times power of Elgar unit)
- Unit arrived CHM 1401 Restoration Room noon March 29, 2005
- Be connected to building by Jim Yee - March 29, 30, 31 2005
- Brought "on-line" April 2, 2005
- from Robert, btw, here's their fancy spec sheet (they still sell them): G Series
- contact - And our technical support person at Pacific Power is Mitch Orr, (949) 251-1800 x124.
Mitchel Orr @ - He remembers this box from 20 years ago..
- Message from Robert Garner
Saturday, with the Pacific Power 18 kVA converter in place,
we ran the full 1401 CPU together with the 1402's reader motor.
(Formerly, this was not possible with the Elgar converter.)

Also, the 1402's master AC power relay clicks on nice & briskly now.
The 1402's ferro-resonant transformers even sound happier.

On Weds, we'll re-attach the 1406 extended memory and run a 729.
And if Frank is in, power the 1403 again.
Although we still have more testing to do, we're off to an
auspicious start.

--I'd like to take this opportunity to thank everyone who made
the Pacific Power acquisition possible and their great help:

Dave, Gary - Thanks for recommending the unit to us, shepherding it
during its last months at IBM San Jose, making the Museum aware that
we could bid on it, and providing documentation & technical support
contact information. You guys were right - it's a fine product.

Mitchel (@Pacific Power) - Thanks for answering our long list of
questions, we really appreciate the support! Your unit is still
pulling a load after 30 years!

Mike F - Thanks for the care and feeding of the IBM bid process!

Mike Z (@Exhibit Oasis) - Thanks for moving and installing the unit!

Jim Yee [via wireless connection] - Thanks for the severals days
of installing the new AC power wiring and circuit breakers!

Ed, Allen, Ron [via wireless], Bob, Frank, et al - Thanks for your
patience and critical evaluations as we searched for a replacement to
the Elgar! (Including motor-generator-set cameos. :-)

Grant - Thanks for supporting our decision to bid on the Pacific Power.

Cross your fingers for Weds,

- Robert

The Pacific Power 390G is performing well :-)) We can power up all our equipment simultaneously. See Wednesday April 6th

This unit has replaced the much lower powered Elgar Model 1751s previously installed. :-))

Last updated April 13, 2005
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