A SERVICE OF

logo

Open as PDF
next previous
General Description 2-3
Physical Description
Figure 2-2 BPX Switch Exterior Rear View
Node Cooling
A fan assembly, with three six-inch 48 VDC fans is mounted on a tray at the rear of the BPX switch
shelf (see Figure 2-2). Air for cooling the cards is drawn through an air intake grille located at the
bottom in the front of the enclosure. Air passes up between the vertically-mounted cards and
exhausts at the top, rear of the chassis. All unused slots in the front are filled with blank faceplates
to properly channel airflow.
Node DC Powering
The primary power for a BPX switch node is -48 VDC which is bused across the backplane for use
by all card slots. DC-to-DC converters on each card convert the 48V to lower voltages for use by the
card. The 48 VDC input connects directly to the DC Power Entry Module (PEM). The DC Power
Entry Module (see Figure 2-3) provides a circuit breaker and line filter for the DC input.
14 13 12 11 10
7
B
C
C
-
A
8
B
C
C
-
B
6
9
15
A
S
M
LM
–
3
/T
3
LM
–
3
/T
3
LM
–
3
/T
3
L
M
–
3
/T
3
LM
–
3/T
3
L
M
–
3/T
3
LM
–
3/T
3
LM
–
3
/T3
L
M
–
3/T
3
LM
–
3/T3
L
M
–
3/T
3
L
M
–
3/T
3
LM
–
3/T3
L
M
–
3/T
3
LM
–
3/T
3
5432
1
Fans
Slot #15
Slot #1
Back
Cards
Air
Exhaust
H8017