Ref: 03250424
Title: VAX 8600 Power Supply ECO; Problem with IVECS
Date: 11/88

Copyright 3Com Corporation, 1991.  All rights reserved.

PROBLEM:  We have found at different sites that serious AC
voltage spikes (as much as 2 volts!) were monitored on the 5
volt rail of the VAX 8600, causing a heyday with our IVECS
product.

A Digital engineer on site reported that when the VAX 8000 came
out, a number of ECO's were required on the machines at
installation.   One of them was to correct the fact that the
Unibus chassis in the original machines was mounted such that it
was electrically isolated from the rest of the machine, allowing
ground to "float".

The ECO numbers from Digital are:  KA-86-AA-AD-I-003;  requires
EQ kit EQ-01386-01 and KA-86-AA-AD-004;  requires EQ kit EQ-01406-
01.

If you suspect power problems with a VAX, make sure these ECO's
have been completed on the machine.
