Cisco 2800 Series Краткое руководство по эксплуатации - Страница 24

Просмотреть онлайн или скачать pdf Краткое руководство по эксплуатации для Сетевое оборудование Cisco 2800 Series. Cisco 2800 Series 47 страниц. Cisco ios software configuration
Также для Cisco 2800 Series: Краткое руководство по эксплуатации (13 страниц), Информационный лист (8 страниц), Примечание по применению (41 страниц), Краткое руководство по эксплуатации (45 страниц), Конфигурация (10 страниц), Обзор (27 страниц), Информационный лист (5 страниц), Информационный лист (20 страниц), Настройка (32 страниц)

Печатать страницу
Cisco 2800 Series Краткое руководство по эксплуатации
Approved Scenarios and Scenarios Not Approved for Dual DC Power Supply Configuration
You can connect a single DC power source to either the A input or the B input. If there are dual power sources, connect one
source to the A input and one source to the B input. Both sources must be the same polarity (with respect to ground) and voltage
(within 0.25 volts). Do not connect –DC grounded and +DC grounded dual sources to Cisco 2811, Cisco 2821, and
Cisco 2851 series integrated services routers.
Dual sources with opposite-polarity grounding damage equipment.
Caution
In Figure 21, either the positive source terminal or the negative source terminal is tied to ground.
Figure 21
Connecting to One Source Only—Source A or Source B
A-
+
A+
B+
B-
In Figure 22, source A and source B share common negative terminal connections.
Figure 22
Connecting Source A and Source B with Common Negative Terminals
Va
+
+
Vb
In Figure 23, source A and source B share common positive terminal connections. This is allowed only if Va equals Vb (within
0.25 V).
When connecting source A and source B with common positive terminals, if source A and source B voltages are
Caution
unequal by more than 0.25 V, the higher-voltage source can discharge into the lower-voltage source through the A-
and B- input terminals. Excessive discharging currents through these terminals can cause one or both of the dual
input DC power supply's internal A- or B- fuses to open, resulting in lack of redundancy or system failure. When
source A and source B are within 0.25 V, discharge current is minimal.
24
+
A-
A+
B+
B-
A-
A+
B+
B-