M320 Power Requirements
Table 1 lists the power requirements
for various hardware components when the router is operating
under typical voltage conditions. For PIC power requirements, see
the M320 Multiservice Edge Router PIC Guide.
Table 1: Component
Power Requirements
Component
|
Power Requirement (Watts)
|
Current Requirement (Amps @ –48 VDC)
|
Base system, not including FPCs
and PICs (includes four SIBs, one host subsystem, four power supplies,
cooling system running at normal speed, and craft interface)
|
450 W (approximate)
|
9.4 A (approximate)
|
Type 1 FPC (without PICs)
|
160 W
|
3.3 A
|
Type 2 FPC (without PICs)
|
160 W
|
3.3 A
|
Type 3 FPC (without PICs)
|
160 W
|
3.3 A
|
Host subsystem (Routing Engine and CB)
|
100 W
|
2.1 A
|
SIB
|
38 W
|
0.8 A
|
AC power supply
|
100 W
|
Not applicable.
|
DC power supply
|
40 W
|
0.8 A
|
Cooling system (normal speed)
|
140 W
|
2.9 A
|
Cooling system (full speed)
|
200 W
|
4.0 A
|
You can
use the information in Table 1 and the M320 Multiservice Edge Router PIC Guide to
calculate power consumption for various hardware configurations, input
current from a different source voltage, and thermal output, as shown
in the following examples for a DC-powered router. (For an added safety margin, the examples use a generalized value for PICs
of 0.625 A
@ –48 V each.)
- Power consumption for minimum configuration:
- Base system + 1 FPC + 1 PIC =
- 9.4 A + 3.3 A + 0.625 A = 13.3 A @ –48 VDC
= 638 W DC
- Power consumption for maximum configuration:
- Base system + 1 Host subsystem + 8 FPCs + 32 PICs =
- 9.4 A + 2.1 A + 8(3.3 A) + 32(0.625 A) =
- 9.4 A + 2.1 A + 26.4 A + 20 A = 57.9 A @ –48 VDC
= 2,779 W DC
- Current requirement adjustment for fans running at full
speed (high temperature environment or cooling component failure):
- Calculated system current (X) – Cooling (normal)
+ Cooling (full speed) =
- X A – 2.9 A + 4.0 A =
- X A + 1.1 A
- Input current from a DC source other than –48 VDC
(based on maximum configuration; applies to DC power supply only):
- (–54 VDC input) x (input
current X) = (–48 VDC input) x (input
current Y)
- 54 x X = 48 x 57.9 A
- X = 48 x 57.9 A/54 = 51.5 A
- System thermal output for maximally configured DC-powered router:
- Watts DC/0.293 = BTU/hr
- 2,779/0.293 = 9,484 BTU/hr
- System thermal output for maximally configured AC-powered router:
- Watts DC/85% AC PEM efficiency/0.293 = BTU/hr
- 2,779/0.85/0.293 = 11,158 BTU/hr
Published: 2009-09-26
