Compaq StorageWorks UltraSCSI RAID Enclosure (DS-BA370 Series) User's Guide (EK-BA370-UG. C02, September 1998)

Power Distribution
6–6 UltraSCSI RAID Enclosure
AC Power Buses
AC power distribution to the UltraSCSI shelf power supplies is
distributed over two power buses—bus A and bus B (see Figure 6–4).
Each power bus has an ac power source, a separate ac input box,
power supplies, and power cords.
Figure 6–4 Enclosure AC Power Buses
Although the standard (n+1) power configuration can operate the
subsystem via power bus A (CALLOUT 1), Compaq recommends
using both power buses with two ac power sources—the optimum
power configuration (n+4).
Power bus A (C
ALLOUT 1) uses black power cords and power bus B
(CALLOUT 2) uses grey power cords. These colored cords indicate the
power bus being used:
• AC input box
A
controls power bus A—power supply positions
1A
through
5A
(n+1 configuration in Figure 6–4)
• AC input box
B
controls power bus B— power supply positions
1B
through
4B
(n+4 configuration in Figure 6–4)
n+1 Configuration n+4 Configurations
Figure C
ALLOUTS
1. Power bus A
2. Power bus B
17
11
CXO6301B
19 20 21 22 23 24
13 14 15 16 18
78910 12
123456
A
4A
3A
2A
1A
5A
Shelf 4
Shelf 3
Shelf 2
Shelf 1
1
17
11
CXO6482B
19 20 21 22 23 24
13 14 15 16 18
78910 12
123456
Controller A
Controller B
EMU
PVA
Cache B Cache A
AB
4A
3A
2A
1A
3B
2B
1B
4B
Shelf 4
Shelf 3
Shelf 2
Shelf 1
1
2