System Overview

Physically, a Trident system consists of field-replaceable modules, the baseplates

upon which modules are mounted, field wiring connections, and a TriStation 1131

programmer’s workstation. This section briefly describes these major elements and

provides general specifications.

Field-Replaceable Modules

Modules are field-replaceable units consisting of an electronic assembly in a

protective metal housing.

Field-replaceable modules include:

• Main Processor Module (MP)

• Communication Module (CM)

• Analog Input Module (AI)

• Analog Output Module (AO)

• Digital Input Module (DI)

• Digital Output Module (DO)

• Pulse Input Module (PI)

• Solid-State Relay Output Module (SRO)

• I⁄O Extender Modules (EM)

Each module is fully enclosed to ensure that no components or circuits are

exposed—even when a module is removed from the baseplate. Offset baseplate

connectors make it impossible to plug a module in upside down, and keys on each

module prevent the insertion of modules into incorrect slots.