EX9253 Power System
EX9253 switches uses either AC or DC power supply (see Figure 1 and Figure 4). The switch can support up to six power supplies installed at the rear panel of the chassis in slots labeled PSM0 through PSM5.
Do not mix AC and DC power supplies in the same chassis.
AC Power Supply Description
Each AC power supply weighs approximately 3.4 lb (1.54 kg) and consists of a handle, an ejector lever, an AC appliance inlet, a fan, and an LED to monitor the status of the power supply. Figure 1 shows the power supply and Figure 2 shows the power supply components.
The switch is a pluggable type A equipment installed in a restricted-access location. It has a separate protective earthing terminal (sized for M5 hex screws) provided on the chassis in addition to the grounding pin of the power supply cord. This separate protective earthing terminal must be permanently connected to earth.


1 — Ejector lever | 3 — Status LED |
2 — AC power cord inlet | 4 — Handle |
Each power supply has its own fan and is cooled by its own internal cooling system. EX9253 switches support 800 W and 1600 W AC power supply. The AC power supply supports the low line (90 through 140 VAC) and the high line (180 through 264 VAC) AC power configurations. Each AC power supply has a single AC appliance inlet located on the power supply that requires a dedicated AC power feed. We recommend that you use a customer site circuit breaker rated for 15 A @ 100 VAC or 16 A @ 200 VAC circuit breaker minimum for each AC power supply, or as required by local code. Doing so enables you to operate the switch in any configuration without upgrading the power infrastructure.
AC Power Cord Specifications for an EX9253 Switch
A detachable AC power cord is supplied with the AC power supplies. The coupler is type C13 as described by International Electrotechnical Commission (IEC) standard 60320. The plug end of the power cord fits into the power source outlet that is standard for your geographical location.
The AC power cord provided with each power supply is intended for use with that power supply only and not for any other use.
In North America, AC power cords must not exceed 4.5 meters in length, to comply with National Electrical Code (NEC) Sections 400-8 (NFPA 75, 5-2.2) and 210-52 and Canadian Electrical Code (CEC) Section 4-010(3). The cords supplied with the switch are in compliance.
Table 1 gives the AC power cord specifications for the countries and regions listed in the table.
Country/Region |
Electrical Specifications |
Plug Standards |
Juniper Model Number |
---|---|---|---|
Argentina |
250 VAC, 10 A, 50 Hz |
IRAM 2073 Type RA/3 |
CBL-EX-PWR-C13-AR |
Australia |
250 VAC, 10 A, 50 Hz |
AS/NZZS 3112 Type SAA/3 |
CBL-EX-PWR-C13-AU |
Brazil |
250 VAC, 10 A, 50 Hz |
NBR 14136 Type BR/3 |
CBL-EX-PWR-C13-BR |
China |
250 VAC, 10 A, 50 Hz |
GB 1002-1996 Type PRC/3 |
CBL-EX-PWR-C13-CH |
Europe (except Italy, Switzerland, and United Kingdom) |
250 VAC, 10 A, 50 Hz |
CEE (7) VII Type VIIG |
CBL-EX-PWR-C13-EU |
India |
250 VAC, 10 A, 50 Hz |
IS 1293 Type IND/3 |
CBL-EX-PWR-C13-IN |
Israel |
250 VAC, 10 A, 50 Hz |
SI 32/1971 Type IL/3G |
CBL-EX-PWR-C13-IL |
Italy |
250 VAC, 10 A, 50 Hz |
CEI 23-16 Type I/3G |
CBL-EX-PWR-C13-IT |
Japan |
125 VAC, 12 A, 50 Hz or 60 Hz |
SS-00259 Type VCTF |
CBL-EX-PWR-C13-JP |
Korea |
250 VAC, 10 A, 50 Hz or 60 Hz |
CEE (7) VII Type VIIGK |
CBL-EX-PWR-C13-KR |
North America |
125 VAC, 13 A, 60 Hz |
NEMA 5-15 Type N5-15 |
CBL-EX-PWR-C13-US |
South Africa |
250 VAC, 10 A, 50 Hz |
SABS 164/1:1992 Type ZA/13 |
CBL-EX-PWR-C13-SA |
Switzerland |
250 VAC, 10 A, 50 Hz |
SEV 6534-2 Type 12G |
CBL-EX-PWR-C13-SZ |
Taiwan |
125 VAC, 11 A and 15 A, 50 Hz |
NEMA 5-15P Type N5-15P |
CBL-EX-PWR-C13-TW |
United Kingdom |
250 VAC, 10 A, 50 Hz |
BS 1363/A Type BS89/13 |
CBL-EX-PWR-C13-UK |
Figure 3 illustrates the plug on the power cord for some of the countries or regions listed in Table 1.

AC Power Supply Specifications for EX9253 Switches
Table 2 lists the AC power system electrical specifications.
Item |
Specification |
---|---|
AC input voltage |
Operating range:
|
AC input line frequency |
50 through 60 Hz (nominal) |
AC system current rating |
25 A |
AC system input power |
2500 W |
Table 3 lists the AC power supply electrical specifications.
Item |
Specification |
---|---|
Maximum output power |
|
AC input voltage |
Operating range:
|
AC input line frequency |
50 through 60 Hz (nominal) |
AC input current rating |
10 A@100 VAC through 240 VAC |
DC Power Supply Description
Each DC power supply weighs approximately 4.4 lb (1.99 kg) and consists of a handle, an ejector lever, a status LED, and a terminal block that provides a single DC input (–48- VDC and return) that requires a dedicated customer-site circuit breaker. We recommend that you use a dedicated customer-site circuit breaker rated for 40 A (–48 VDC) minimum, or as required by local code.
Figure 4 shows the power supply and Figure 5 shows the power supply components.


1 — Ejector lever | 3 — DC power terminals |
2 — Status LED | 4 — Handle |
Each power supply has its own fan and is cooled by its own internal cooling system. EX9253 switches support 1100 W DC power supply. Each DC power supply has terminals located on the power supply that require dedicated feeds. We recommend that you use a dedicated customer-site circuit breaker rated for 40 A (–48 VDC) minimum, or as required by local code. Doing so enables you to operate the switch in any configuration without upgrading the power infrastructure.
DC Power Supply Specifications for EX9253 Switches
Table 4 lists the DC power system electrical specifications.
Item |
Specification |
---|---|
DC input voltage |
Operating range: –40 through –72 VDC |
DC system input current rating |
54 A @ –48 VDC (maximum) |
DC system input power |
2500 W |
Table 5 lists the DC power supply electrical specifications.
Item |
Specification |
---|---|
Maximum output power |
1100 W |
DC input voltage |
Minimum: –40 VDC Nominal: –48 VDC, –60 VDC Operating range: –40 through –72 VDC |
DC input current rating |
32 A @ –48 VDC |
Power Requirements for EX9253 Components
Table 6 lists the power requirements for various hardware components when the switch is operating under typical and maximum voltage conditions.
Component |
Power Requirement at 25° C (Watts; Typical) |
Power Requirement at 55° C (Watts; Maximum) |
---|---|---|
EX9253-6Q12C line card |
740 W |
800 W |
EX9253-6Q12C-M line card |
770 W |
835 W |
Routing Engine |
58 W |
65 W |
Fan tray |
20 W |
95 W |
Calculating System Thermal Output
After you have calculated the power consumption for your configuration, you can use that information to determine the system thermal output (BTUs per hour). Multiply the power consumption in watts by 3.41 to compute the system thermal output.