The 3500/20 Rack Interface Module (RIM) serves as the primary interface to the 3500 rack, enabling configuration and retrieval of machinery information. It operates using a proprietary protocol and must be located in slot 1 of the rack, adjacent to the power supplies.
While the RIM provides essential functions for the rack, it is not part of the critical monitoring path and does not affect the normal operation of the monitoring system. One RIM is required per rack, and for Triple Modular Redundant (TMR) applications, a TMR version of the RIM is needed. This TMR RIM performs monitor channel comparison and implements monitor voting. It ensures that the information from the three redundant monitors remains within a configured tolerance. If one monitor deviates from the others, the TMR RIM flags the error and records an event in the System Event List.
Specifications
Inputs
Power Consumption: 4.75 watts (typical)
Data Front Panel:
Standard RS232 serial communications
Data Rate: 38.4 k baud
I/O Modules:
RS232/RS422 serial communications
Internal Modem Communications:
Data Rate: 38.4 k baud (serial)
14.4 k baud (internal modem)
Outputs
Front Panel LEDs:
OK LED: Indicates proper RIM operation
TX/RX LED: Indicates communication with other modules in the 3500 rack
TM LED: Indicates when the rack is in Trip Multiply
CONFIG OK LED: Indicates a valid rack configuration
I/O Module OK Relay:
Indicates when the rack is functioning normally or if a fault is detected
User-selectable “OPEN” or “CLOSED” contact to annunciate a “NOT OK” condition
Relay Rating: 5A @ 24V DC/120V AC, 120W/600VA switched power
Arc Suppressors: Provided for relay contacts
Controls
Front Panel Controls:
Rack Reset Button: Clears latched alarms and Timed OK Channel Defeat, same as “Rack Reset” contact on I/O module
Address Switch: Sets the rack address (up to 63 addresses)
Configuration Keylock:
RUN Mode: Normal operation, locks out configuration changes
PROGRAM Mode: Allows configuration changes (local or remote)
The key can be removed in either position, enabling remote configuration or restricting unauthorized changes
I/O Module System Contacts:
Trip Multiply: Places the rack in Trip Multiply
Alarm Inhibit: Inhibits all alarms in the rack
Rack Reset: Clears latched alarms and Timed OK Channel Defeat