IS220PRTDH1B RTD Input Pack: Factory-Packaged Stock

Offered here as new surplus in factory packaging, the IS220PRTDH1B is the H1B revision of GE's Mark VIe RTD input pack. It performs the same task as every PRTD pack — measuring the resistance of field RTDs and delivering calibrated temperature data to the Mark VIe controller — but carries the hardware revision level that many operating sites now standardize on for their RTD channels.

Physically, the pack is a self-powered distributed I/O module that mounts on a TRTD-series RTD terminal board. It talks to the controller through dual RJ45 IONet ports, takes power on a three-pin connector with an onboard soft-start, and passes analog data across a 37-pin connector to the terminal board. One pack handles up to eight three-wire RTDs; two packs on a single TRTD board extend that to sixteen. Excitation is a multiplexed 10 mA DC current, and the 14-bit A/D converter samples each channel four times per second normally, or 25 times per second in fast-scan mode.

Rule Out the Sensor and Wiring First

A factory-sealed spare is worth keeping unopened until you are sure you need it — so confirm the diagnosis before you break the seal. On RTD temperature inputs, the most common bad pack turns out to be a bad loop:

• Sensor: an aged or cracked RTD element reads open, high, or erratic. Cross-check against a nearby sensor.
• Wiring: keep the two-way lead resistance near or below 15 ohms; a sensor up to 300 m (984 ft) out leaves plenty of cable to corrode or chafe.
• Terminal board: inspect the TRTD landing points and the board revision — the terminal board provides the transient protection and filtering for the channel.
• Power and IONet: a missing or resetting pack often traces to its power feed or its Ethernet path, not to the silicon.

The front-panel Power and ATTN LEDs, together with ToolboxST diagnostics, are your fastest triage tools. Replace the pack only once the sensor, wiring, terminal board, power, and network are cleared.

H1A vs H1B: Matching the Right Revision

In the IS220PRTDH1B number, IS220 is the distributed I/O pack family, PRTD is the RTD input function, and H1B is the group-and-revision suffix. The trailing letter reflects the hardware revision, so H1B follows H1A in the sequence. The two are the same functional pack, but you should always match the suffix and the revision stamped on the unit you are replacing, and confirm the pairing with your terminal board revision. There is a related detail worth knowing on the RTD side: the TRTD terminal board comes in revisions tuned to the pack's scan rate — one for the standard scan rate and another with lighter filtering for fast-scan operation — so terminal board and pack revision should be considered together. Our GE Speedtronic Part Number Decoder covers the numbering in depth.

Terminal Boards and Neighboring Packs

The PRTD's closest relative is the PTCC thermocouple pack; together they cover most turbine temperature measurement. For background on how GE moved from the Mark V generation to the IS200/IS220 world, see Mark V vs Mark VI: DS200 to IS200. The full catalog lives under GE Mark VI IS200 Boards and GE Speedtronic Turbine Control Boards.

Building a Complete RFQ

• The exact part number and suffix, IS220PRTDH1B, plus the revision on the label.
• A label photo where possible.
• Turbine model and Mark VIe generation.
• Quantity and urgency.

Request Your IS220PRTDH1B Quote

This IS220PRTDH1B is new-surplus, factory-packaged stock, backed by the warranty stated below. Press Request a Quote and we will get back to you within 24 hours, with worldwide DDP shipping and purchase orders accepted.