Juniper MX2008 Hardware Manual page 225

Table 97 on page 225
deficit).
Table 97: Calculating DC Power Budget
Power Supply Module
MX2000 DC PSM 60 A (feed to each input)
MX2000 DC PSM 80 A or DC PSM (240
V China) (feed to each input)
3. Calculate input power. Divide the total output requirement by the efficiency of the PSM as shown in
Table 98 on page 225.
Table 98: Calculating DC Input Power
Power Supply Module
MX2000 DC PSM 60 A
MX2000 DC PSM 80 A or DC
PSM (240 V China)
4. Calculate thermal output (BTUs). Multiply the input power requirement (in watts) by 3.41 as shown in
Table 99 on page 225.
Table 99: Calculating DC Thermal Output
Power Distribution Module
MX2000 DC PDM
SEE ALSO
lists the PSMs, their maximum output power, and unused power (or a power
Maximum Output Power
of Power Supply Module
(Watt)
2100
2500
Power Supply
Module Efficiency
91%
91%
Thermal Output (BTUs per hour)
34.5 KW divided by 0.91 * 3.41 = 129,280 BTU/hr.
34.5 KW of output power consumed by the chassis. This is the
maximum output the chassis can consume in a redundant
configuration. The input power is 16.5 divided by 0.91 =
37.9 KW.
Maximum Output Power for
System (Watt)—Including
Redundant Capacity
18,900
22,500
Output Power
Requirement Input Power Requirement
(Watt)—per PSM (Watt)—per PSM
2100 2307
2500 2747
225