Cisco AP776A - Nexus Converged Network Switch 5020 Configuration Manual page 282

Power Supply Configuration Modes
S e n d d o c u m e n t a t i o n c o m m e n t s t o m d s f e e d b a c k - d o c @ c i s c o . c o m
Table 11-1
Scenario
1
2
3
1. W = Watts
Table 11-2
Scenario
1
2
3
1. W = Watts
2.
Cisco MDS 9000 Family CLI Configuration Guide
11-12
Redundant Mode Power Supply Scenarios
Power Current
Supply 1 Usage
1
(W) (W)
2500 2000
2500 2000
2500 2000
Combined mode—The total power is twice the lesser of the two power supply capacities.
b.
For example, suppose you have the following usage figures configured:
Power supply 1 = 2500 W
Additional Power supply 2 = not used
Current Usage = 2000 W
Current capacity = 2500 W
Then the following three scenarios will differ as specified (see
Scenario 1: If 1800 W is added as power supply 2, then the capacity increases to 3600 W.
Reason: 3600 W is twice the minimum (1800 W).
Scenario 2: If 2200 W is added as power supply 2, then the current capacity increases to
4400 W.
Reason: 4400 W is twice the minimum (2200 W).
Scenario 3: If 3000 W is added as power supply 2, then the current capacity increases to
5000 W.
Reason: 5000 W is twice the minimum (2500 W).
Combined Mode Power Supply Scenarios
Power Current
Supply 1 Usage
1
(W) (W)
2500 2000
2500 2000
2500 2000
When you change the configuration from combined to redundant mode and the system detects a
power supply that has a capacity lower than the current usage, the power supply is shut down. If both
power supplies have a lower capacity than the current system usage, the configuration is not allowed.
Several configuration scenarios are summarized in
Scenario 1: You have the following usage figures configured:
Power supply 1 = 2500 W
Additional Power supply 2 = 1800 W
Current Usage = 2000 W
Current mode = combined mode (so current capacity is 3600 W)
Insertion of New
Power Capacity
Supply 2 (W) (W)
1800 2500
2200 2200
3300 2500
Insertion of New
Power Capacity
Supply 2 (W) (W)
1800 3600
2200 4400
3300 5000
Table 11-3.
Chapter 11 Managing System Hardware
Action Taken by Switch
Power supply 2 is shut down.
Capacity becomes 2200 W.
Capacity remains the same.
Table 11-2):
Action Taken by Switch
Power is never shut down. The
new capacity is changed.
OL-18084-01, Cisco MDS NX-OS Release 4.x