GE IS220PDOAH1A Discrete Output Pack Unit

Module Feature

IS220PDOAH1A is the PDOA discrete output pack for GE Mark VIe Speedtronic turbine control system.

It works together with TRLY terminal boards to provide up to 12 relay output channels. It communicates with the main controller over dual Ethernet I/O bus, converts logic commands into contact drive signals for solenoid valves, auxiliary relays and turbine interlock actuators. It supports solid-state and mechanical relay terminal variants and is widely used in gas and steam turbine control cabinets.

Working principle

The main controller sends output setpoints via Ethernet I/O network.

The module receives commands and drives corresponding relay channels on the mating terminal board. It feeds back relay status to the controller for circuit health monitoring. It participates in turbine safety interlock, valve control and auxiliary equipment start-stop logic.

Onboard components

I/O processor, Ethernet communication circuit, output drive logic, backplane connector, status LED array.

LED indicators

Onboard LEDs show power, network link, module run and channel fault status.

Hardware self‑diagnosis

Continuous diagnosis detects communication failure, channel circuit fault and pack hardware anomaly, alarms are displayed and logged in ToolboxST.

Programming software

ToolboxST, used for signal tag assignment, logic configuration and fault event review.

Electrical & Process Parameters

Model:IS220PDOAH1A Brand:GE Device type:Discrete output I/O pack System:Mark VIe Speedtronic Output:12 relay channels (with TRLY terminal board) Communication:Dual Ethernet Function:Field relay and interlock actuator control for turbine system

Mechanical & Structure

Mounting:Install on Mark VIe I/O backplane

Protection class:IP20

Housing:PCB assembly with metal shielding frame

Environmental

Operating temperature:0℃ ~ +60℃

Storage temperature:-40℃ ~ +85℃

Ambient humidity:5~95% non‑condensing

Certification:CE

Status:Original GE turbine control spare

Installation

Disconnect cabinet power before replacement, insert pack into the designated I/O slot and secure fasteners.

Connect Ethernet I/O cables and mating TRLY terminal board wiring according to schematic. Download configuration and verify each output channel action before commissioning.

Interface

Dual Ethernet port, backplane bus connector, terminal board signal connector.

Diagnostic

No network communication: Ethernet cable damaged, IP mismatch or backplane pin fault.

Output fails to actuate: Terminal board relay failure, open field load circuit.

Channel feedback abnormal: Loose wiring or terminal board damage.

Module fault alarm: Pack hardware failure.

Product Brief

GE IS220PDOAH1A Mark VIe PDOA discrete output pack, 12-channel relay control module for gas and steam turbine interlock and auxiliary actuator control.