User's Manual

044-05156 Rev C 47
PWM VS. Temperature
PWM (%) Maximum Temperature
0 +41°C or less
15 +42°C
25 +43°C
35 +44°C
45 +45°C
55 +46°C
65 +47°C
75 +48°C
85 +49°C
100 +50°C or greater
There are three fan fault frequency thresholds related to speed control.
Fan Fault Thresholds
PWM (%) Fan Fault Threshold
100 - 50 40Hz
49 - 20 15Hz
< 20 10Hz
Each fan sense input is measured. If the fan frequency(s) is below the threshold (for the operating mode) for a
continuous period of 1-minute a fan fault is reported to the DALI interface. Any change in fan status is reported to
the BTS in real-time via the I
2
C interface. The fan fault on the DALI is cleared when all of the fan frequencies
maintain above threshold performance for a period of 30 seconds. Alarm monitoring will halt if the fan control is
0%PWM. When this occurs, the current alarm status latches.
The cabinet fan interface is a DB15 Female connector. The interface provides fan monitor inputs, and fan control /
status outputs.
The fan control circuitry provides a 0 to 10Vdc signal to adjust the fan speed.
Pin # Description Pin # Description
1 Ground 9 Fan 0 Sense
2 Fan1 Sense 10 Fan 2 Sense
3 Fan3 Sense 11 I
2
C Serial I/O Data
4 I
2
C Serial I/O Clock 12 Ground
5 Ground 13 No Connection
6 No Connection 14 Fan 3 Speed Control
7 Fan 2 Speed Control 15 Fan 1 Speed Control
8 Fan 0 Speed Control
4.9.4.3 RS-232 Interface (J21)
The front panel of the SIM provides a RS-232 serial communication port. The RS-232 port provides for upgrading
firmware, and displaying system status and configuration. These tasks are performed via PC and interface
software.
Upgrading firmware
Display all DALI alarms
Display all DLNA, MCPA and SIM temperatures in °C