19 Jun
2014
19 Jun
'14
10:20 a.m.
Rotary converters are effective but pricy. Solid
state variable frequency motor controllers (basic ones) are a lot more economical. They
will do for a few kW of 3-phase power. They will also serve if you need a different
frequency ? not usually a consideration but it matters if you have an old Cyber, or
possibly some military surplus gear.
Quite a few big iron systems (not that toy stuff DEC made) use higher
frequency power (400 or 415 Hz). CDC and Cray, as mentioned, but also
IBM and some of the Japanese machines.
The low end Cybers (810, 825, 830) *should* run on 60 Hz, as the
transformers are actually spec'd to work down there. No doubt more
capacitors for filtering would be required, hanging off the side.
--
Will