MOUNTING AS 3904990 - Caterpillar

Table 1
Product Link Contact Descriptions    
Main Connector Contact (70 pin)    Description of the Input    
45     Spare Digital Input 1    
46     Spare Digital Input 2    
47     Spare Digital Input 3    
55     Spare Digital Input 4    See the Systems Operation, Troubleshooting, Testing and Adjusting, "System Schematic" for a diagram of the digital input circuitry. PL321 Digital Input Configuration
PL321 digital input configuration is done through Cat ET.
Illustration 1 g02290993
"Digital Input Configuration" screen
Table 2
Digital Input 1, 2, 3, or 4    
Sensor    Definition    Configuration    Notes    
Digital Sensor input one, two, three, or four configuration types.     Digital sensor input one, two, three, or four configuration types defines whether a sensor is attached. And, if attached, the state of the switch contacts under normal operating conditions (Normally Open or Normally Closed).     "Not Installed": The user cannot set the sensor to "Not Installed". No sensor attached to the input.
The user can set the type of sensor by the following methods:
"Not Configured": Sensor may be attached to the input but not in use.
"Normally Closed": Sensor is at a closed (or low) state under normal operating conditions.
"Normally Open": Sensor is at an open (or high) state under normal operating conditions.     The user cannot set the sensor to "Not Installed". "Not Installed" is the factory default.    
Digital Sensor input one, two, three, or four monitoring conditions.     Defines the monitoring condition for the digital input.
An event is recorded and sent to the Equipmentmanager when the following conditions are met:
The digital input is in the alarm state as specified in Digital Sensor input one, two, three, or four type configurations.
For