Technical Documentation
Power Consumption for a DC-Powered MX960 Router
We recommend that you provision at least 116 A (58 A per feed) @ –48 VDC (nominal) for the system when using normal capacity power supplies and 208 A (104A per supply) @ -48 VDC (nominal) for the system when using high capacity power supplies.
If you do not plan to provision the maximal power to the system, you can use the information in Table 1 and Table 2 to calculate the power consumption @ –48 VDC and thermal output for your hardware configuration.
Table 2 lists the power requirements for base DC-powered routers operating under typical voltage conditions and includes nonredundant and redundant power supply configurations.
 | Note: The base DC-powered router includes the midplane, craft interface, and fan trays running at normal speed. |
Table 1: DC Base Router Power Requirements
DC Power Supply Configuration | Power Requirement (Watts) | Current Requirement (Amps @ –48 VDC) |
|---|---|---|
Nonredundant DC configuration includes two DC power supplies, the midplane, craft interface, and fan trays running at normal speed. | 450 W (approximate) | 8.3 A (approximate) |
Redundant DC configuration includes four DC power supplies, the midplane, craft interface, and fan trays running at normal speed. | 450 W (approximate) | 8.3 A (approximate) |
Table 2: Component DC Power Requirements
Component | Power Requirement (Watts) | Current Requirement (Amps @ –48 VDC) |
|---|---|---|
SCB | 150 W | 3.1 A |
Routing Engine | 90 W | 1.9 A |
Cooling system (full speed – normal speed) | 600 W – 450 W = 150 W | 4.2 A |
High-capacity cooling system (Full speed - normal speed) | 640 W - 450 W = 190 W | 5.0 A |
DPC—Generalized typical value | 312 W | 6.5 A |
DPC—Generalized maximum value | 365 W | 7.6 A |
FPC2 (without PICs) | 110 W | 2.3 A |
FPC3 (without PICs) | 180 W | 3.8 A |
MPC (fixed configuration) | 440 W | 9.17 A |
MPC (without MICs) | 294 W | 6.13 A |
These examples use generalized values for DPCs. For exact DPC,
MPC, MIC, and PIC power requirements, see the MX Series 3D Universal Edge Routers Line Card Guide 
.
Typical power consumption for DC-powered routers:
- Power consumption for minimum configuration:Base router and two power supplies + 2 SCBs + 1 Routing Engine + 1 DPC—Generalized typical value =8.3 A +2( 3.1) A + 1.9 A + 6.5 A = 22.9 A @ –48 VDC = 1,099 W DC
- Power
consumption for maximum configuration:Base router and four power supplies + fan tray at full speed + 2 SCBs + 2 Routing Engines + 12 DPCs—Generalized maximum value =8.3 A + 4.2 A + 2(3.1 A) + 2(1.9 A) + 12(7.6 A) = 8.3 A + 4.2 A + 6.2 A + 3.8 A + 91.2 A = 113.7 A @ –48 VDC = 5458 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 – 8.3 A + 12.5 A =X A + 4.2 A
- Input current from a DC source other than –48 VDC
(based on maximum configuration; applies to DC power supply only):(–54 VDC input) * (input current X) = (–48 VDC input) * (input current Y)54 * X = 48 * 106.1 AX = 48 * 106.1 A/54 = 94.3 A
- Example of calculating system thermal output:Watts DC * 3.41 = BTU/hr5093 * 3.41= 17,367 BTU/hr
