Calculating Power Requirements For Mx240 Routers - Juniper MX240 Hardware Manual

196

Calculating Power Requirements for MX240 Routers

The information in this topic helps you determine which power supplies are suitable for various
configurations, as well as which power supplies are not suitable because output power is exceeded. You
determine suitability by subtracting the total power draw from the maximum output of the power supplies.
Afterward, the required input power is calculated. Finally, you calculate the thermal output. A sample
configuration is provided in Table 83 on page 197.
We recommend that you provision power according to the maximum input current listed in the power
supply electrical specifications (see "AC Power Supply Electrical Specifications for the MX240 Router" on
page 50 and "DC Power Supply Electrical Specifications for the MX240 Router" on page 58).
Use the following procedures to calculate the power requirement:
1. Calculate the power requirement.
2. Evaluate the power budget.
3. Calculate input power.
4. Calculate thermal output (BTUs) for cooling requirements.