Juniper MX240 - Table 73: Calculating Power Budget; Table 74: Calculating Input Power Examples

Table 73 on page 139 lists the power supplies, their maximumoutput power,and unused
power (or a power deficit). See “DC Power Supply Electrical Specifications for the
MX240 Router” on page 143 and “AC Power Supply Electrical Specifications for the
MX240 Router” on page 127 for more information about the MX240 power supply
electrical specifications.
Table 73: Calculating Power Budget
Unused Power
1
Maximum System Output
PowerPower Supply
654 W2054 WMX240 AC Normal-capacity (low-line)
190 W1590 WMX240 AC Normal-capacity (high-line)
934 W2334 WMX240 AC High-capacity (low-line)
650 W2050 WMX240 AC High-capacity (high-line)
200 W1600 WMX240 DC Normal-capacity
1000 W2400 WMX240 DC High-capacity (DIP=0)
1200 W2600 WMX240 DC High-capacity (DIP=1)
1
For this configuration, output power excluding the cooling system is 1400 W.
3. Calculate input power. In this step, the input power requirements for the example
configuration are calculated. To do this, divide the total output requirement by the
efficiency of the power supply as shown in Table 74 on page 139.
Table 74: Calculating Input Power Examples
Input Power Requirement
2
Power Supply Efficiency
1
Power Supply
1747 W85 %MX240 AC Normal-capacity (high-line)
1669 W89 %MX240 AC High-capacity (high-line)
1515 W~98 %MX240 DC Normal-capacity
1515 W~98 %MX240 DC High-capacity
1
These values are at full load and nominal voltage.
2
For this configuration, total power is 1485 W.
4. Calculate thermal output (BTUs). To calculate this, multiply the input power
requirement (in watts) by 3.41. See Table 75 on page 140.
139Copyright © 2017, Juniper Networks, Inc.
Chapter 12: AC Power Requirements and Specifications