Dell PowerConnect B - MLXe 8 Hardware Installation Guide - Page 119

Managing the cooling system 5 Managing the cooling system This section provides configuration, management, and monitoring information about router cooling systems. Configuring the cooling system Your router is pre-configured with default settings for all cooling system parameters. Although no initial configuration of the cooling system is necessary, you can change the settings of the following cooling system parameters: • Low and high temperature thresholds for modules and fan speeds • Interval at which the system polls the temperature sensors on the module for a reading Changing temperature thresholds for modules and fan speeds The cooling system includes fans that operate at four speeds: low, medium, medium-high, and high. In general, each fan speed, (except for low), has a low and high temperature threshold associated with it, as shown in Figure 64. The low fan speed has a high temperature threshold only. FIGURE 64 Fan speeds and temperature thresholds High, 60 deg. Low, 67 deg. High, 80 deg. Low Speed Med-High Speed Operating Temperature 50 55 60 65 70 75 80 85 90 95 Medium Speed High Speed Low 57, deg. High, 70 deg. Low, 77 deg. High, 85 deg. The low and high temperature thresholds allow the router to determine the speed at which the fans should operate. In general, the fans operate according to these guidelines: • If the temperature of all modules falls between the low and high thresholds for a fan speed, the fan continues to operate at that speed. • If the temperature of a management module, switch fabric module, or two interface modules exceeds the high threshold specified for a fan speed, the fan changes to the next higher speed. If the temperature of any of the modules exceeds the high threshold for the high speed, the router shuts down the modules to prevent damage. The router also sends a warning message to the system log and an SNMP trap. For information about viewing the warning messages, refer to "Displaying temperature warnings" on page 112. • The frequency with which the temperature is checked is determined by the setting of the temp-poll-period command. For information about temp-poll-period command, refer to "Changing the temperature polling interval" on page 110. • If the temperature of a management module, switch fabric module, and interface modules falls below the low threshold for a fan speed, the fan changes to the next lower speed. If the temperature of all modules falls below the high threshold for the low speed, the fan operates at the low speed. PowerConnect B-MLXe Hardware Installation Guide 107 53-1002111-01