[R-390] R390A power cord specifications

[John Wendler]

Does anyone have an authoritative specification on the power cord for the
as-shipped R390A?  I do not see a length requirement in MIL-R-13947B and
have not yet spotted a part number in the manuals that I looked at.

The power requirement (275 Watts, max) in conjunction with the lower
voltage (115 VAC) says the maximum current that cord will carry is about
2.4 Amps.  The brackets that capture the power cord on the rear panel set a
maximum outer insulation diameter of approximately 0.36 inches. 18/3 SOOW
should work, but I was wondering about the historical lore.  I expect that
installers would have chopped or replaced as necessary for a neat
installation.

As an aside, one of my units came with a plug that had a rotatable ground
pin for use with either 2-wire or 3-wire power outlets.  Point the pin
forward for 3-wire outlets; rotate it 90 degrees out of the way for the
2-wire outlets.  The ground wire is secured by a lug to the screw that the
pin rotates around.