22 Jun
2010
22 Jun
'10
9:48 p.m.
On Tue, Jun 22, 2010 at 1:08 PM, Rob Jarratt
<robert.jarratt at ntlworld.com> wrote:
I have a MicroVAX 3400. It uses quite a lot of power
compared to my other
MicroVAXen (about 180-200W). It has an M9060 Load Module installed and I
understand that this is needed to give the power supplies enough load to
work correctly. However, if I have enough stuff already in the machine then
it would seem that this module is just sucking up power needlessly. How much
stuff do you need in the machine to make the M9060 redundant?
Incidentally, anyone know why this machine has two PSUs if they are not (as
I have read somewhere) redundant?
The power planes of a BA213 backplane are split into a left half
(slots 7 to 12) and a right half (slots 1 to 6). Each power suppy
only supplies its half of the backplane. If you look at the bare
backplane there are power bus bars at the top and and bottom of the
slots which are visibly split into a left half and a right half.
The BA213 Enclosure Maintenance manual (EK-189AA-MG-001) says that a
M9060 load module must be installed in one of the backplane slots 7
through 12 if the continuous minimum current drawn on the second power
supply is less than 5 amperes. If the minimum current of 5 amperes is
not reached, the power supply enters an error mode and shuts down the
system.