IS220PDIAH1B: Discrete Input Module for Mark VIe and Mark VIeS

This used IS220PDIAH1B has been cleaned and fully tested ahead of sale, with a 1-year warranty. GE's IS220 pack family, including PDIA, is used across both the Mark VIe and Mark VIeS Speedtronic control platforms — the pack's job is the same in either case: it's the discrete contact input pack, mounted directly on a discrete input terminal board via a single DC-37 pin connector, exchanging data with the <R>, <S>, or <T> controller over the I/O Ethernet network (IONet) through dual RJ-45 ports.

PDIA accepts up to 24 contact inputs plus terminal-board feedback signals, supporting three input voltage levels depending on the terminal board fitted (TBCIH1, H2, or H3) and a separate path for the isolated, voltage-sensing TICI board. Compatible terminal boards are TBCI, TICI, and STCI, but not the DIN-rail mounted DTCI board. Each of the 24 inputs has its own comparator, opto-isolated supply, filtering and hysteresis, and a dedicated yellow status LED; optical isolation is rated to 1500 V, with a 4 ms hardware filter and a -40 to +70°C operating range. GE documents this pack in the GEH-6721 Mark VIe Control System Guide.

Diagnose Before You Replace It

• Since the terminal board does the first stage of signal conditioning, a bad input reading is frequently a field wiring, contact, or terminal board issue — not the pack.
• A documented field case on this exact pack type involved intermittent IONet communication loss and a hardware watchdog fault, with no visible problem at the pack; replacing switches, cables, and even the pack itself did not resolve it. The fault was eventually traced to the terminal board after swapping the pack onto a different one — a reminder that the swap test should come before, not after, a parts order.
• Check IONet cable ends and connectors for corrosion or discoloration, and confirm cable bend radius is within spec.
• Confirm your Simplex, Dual, or TMR configuration, since expected behavior differs across the three.
• Rule out heat, dust, and humidity in the control compartment — widely reported as the most common driver of Mark VIe I/O pack failures — before assuming a single pack is simply bad.

What the Suffix Tells You

IS220 marks a Mark VIe/Mark VIeS distributed I/O pack, PDIA the contact input function, H1 the design generation, and B a hardware/processor revision beyond the original H1A. Match the complete part number and revision to your terminal board and ControlST project. Our GE Speedtronic Part Number Decoder covers GE's naming convention in full.

Related Packs and Terminal Boards

PDIA pairs with TBCI/TICI/STCI-family terminal boards. For discrete outputs, see the related PDOA pack, or PDIO for combined input and output on one terminal board. Our GE Mark VI IS200 Boards collection lists compatible terminal boards.

What to Send Us for a Quote

• Full part number with suffix (IS220PDIAH1B)
• A photo of the label
• Turbine model and Mark control generation (VIe or VIeS)
• Quantity
• Urgency of the request

We respond within 24 hours, ship worldwide DDP, and accept purchase orders. Request a Quote and our team will confirm fit and availability directly with you.