Power Connections
25
Connecting Cables to Cisco 3800 Series Routers
OL-5970-02
Caution
Dual sources with opposite-polarity grounding damage equipment.
In
Figure 16
, either the positive source terminal or the negative source terminal is tied to ground
.
Figure 16
Connecting to One Source Only—Source A or Source B
In
Figure 17
, source A and source B share common negative terminal connections.
Figure 17
Connecting Source A and Source B with Common Negative Terminals
In
Figure 18
, source A and source B share common positive terminal connections. This configuration is
allowed only if Va equals Vb (within 0.25 V).
Caution
If source A and source B are wired with common positive terminals and their voltages are unequal by
more than 0.25 V, the higher-voltage source can discharge into the lower-voltage source through the
negative terminals. Excessive discharging currents through these terminals can actuate one or both of
the dual- input DC power supply’s internal A– or B– fuses, resulting in lack of redundancy or system
failure. When source A and source B are within 0.25 V, discharge current is minimal.
A-
127037
A+
B+
B-
+
A-
A+
B+
B-
+
A-
127039
A+
B+
B-
Va
Vb
+
+
Содержание 3800 Series
Страница 7: ...Safety Warnings 7 Introduction to Hardware Documentation OL 5965 01 ...
Страница 8: ...Safety Warnings 8 Introduction to Hardware Documentation OL 5965 01 ...
Страница 30: ...Regulatory Compliance 16 Overview of Cisco 3800 Series Routers OL 5966 01 ...
Страница 48: ...Grounding the Router 18 Installing Cisco 3800 Series Routers in an Equipment Rack OL 5969 01 ...
Страница 80: ...More Troubleshooting Help 50 Troubleshooting Cisco 3800 Series Routers OL 5972 01 ...
Страница 102: ...Removing SFP Modules 72 Installing SFP Modules in Cisco 3800 Series Routers OL 5968 01 ...