Themis RES-XR4-3U, Installation Manual

Page: 83 / 184

2—Installation and Operation
2-21
Themis Computer
2.2 Power Supply
Power supplies may be ordered in pairs to provide N+1 load-sharing redundancy.
Systems ordered with only one power supply module are supplied with a
dummy/blank module installed in the other power supply bay. In such configuration
there is no redundancy in the power supply subsystem. This also applies to the MIL-
STD-461 spec’ed power supplies, both AC and DC, because a single power supply
is double wide, and occupies both power supply bays.
Each load-sharing (N+1 redundant) power supply can be hot-swapped while the sys-
tem is still on and operational.
2.2.1 DC Power Supply Option
The optional DC power supplies are available in 28VDC and 48VDC. They have the
same configuration and physical size as the AC power supplies, except that the MIL-
STD-461 spec’ed power supply is double wide, occupying both power supply bays.
The MIL-STD-461 power supply therefore does not offer redundancy. (See Figure
2-1 on page 2-2).
Each DC power supply is fitted with a Positronics PLB06M socket which mates with
a PLB06F cable connector on the supplied cable. The supplied cable has three leads,
each 80cm long, and is terminated with Y-type lugs, SVS5-4 or equivalent.
Figure 2-19.
DC Power Supplies