Description
GE IS230SNCIH6A | Contact Input Module | Mark VIe Discrete Signal Monitoring
Key Technical Specifications
| Parameter | Specification |
|---|---|
| Product Model | IS230SNCIH6A |
| Manufacturer | GE Energy / General Electric |
| Control System | Mark VIe / Mark VIeS |
| Functional Type | Contact Input Module |
| Input Type | Discrete contact inputs |
| Number of Inputs | 24 |
| Nominal Excitation | 125 VDC |
| Input Threshold | Approximately 50% of excitation voltage |
| Redundancy | Simplex |
| I/O Pack | PDIA |
| Terminal Board | STCI |
| Signal Conditioning | Noise/surge suppression |
| Assembly | IS230 standard module |
| Operating Temperature | -30°C to +65°C |
| Humidity | 5–95% RH, non-condensing |
The 24-input and 125 VDC figures are supported by the technical description for the SNCIH6A family. The operating-temperature and humidity figures are also reported for this part.
Product Introduction
The GE IS230SNCIH6A is a Mark VIe Simplex Contact Input Module designed to acquire discrete field contact states. It is used for signals such as switch positions, relay contacts, auxiliary contacts, permissives, alarms, and other two-state turbine-system indications. The documented configuration uses an STCI-type terminal interface together with a PDIA I/O pack.
The GE IS230SNCIH6A is specifically associated with a nominal 125 VDC contact excitation and accepts 24 contact inputs. Its input threshold is approximately 50% of the applied excitation voltage, so the actual field circuit should be checked rather than assuming that every 24 VDC or 125 VDC discrete signal is interchangeable.
IS230SNCIH6A
Application Scenarios & Field Pitfalls — Engineer’s Perspective
Engineering Pain Point
The main replacement risk is confusing the SNCIH6A with other Mark VIe discrete-input variants. GE uses closely related terminal-board and I/O-pack combinations, but their electrical input characteristics can differ.
Typical Applications
- Turbine auxiliary status monitoring — Collects discrete states from switches and auxiliary contacts.
- Protection permissives — Interfaces contact-based permissive and interlock signals with Mark VIe logic.
- Alarm/status acquisition — Monitors relay contacts and equipment operating states.
- Gas and steam turbine control cabinets — Provides field-side discrete input acquisition within a Mark VIe installation.
Technical Pitfalls to Avoid
- Do not assume it is a 24 VDC input module. Current listings sometimes describe the IS230SNCIH6A as a generic 24 VDC digital input. The stronger technical reference identifies the H6A configuration with 125 VDC nominal excitation.
- Do not confuse SNCIH6A with STCIH6A. The two are closely related Mark VIe discrete-input products. The STCIH6A is documented as an STCI terminal board plus PDIA I/O pack, while the SNCIH6A is identified as its cousin/contact-input configuration.
- Do not assume redundancy. The H6A configuration is identified as Simplex. If the existing application uses dual or TMR architecture, verify the complete I/O arrangement before ordering a replacement.
- Verify the actual field excitation. A contact-input module detects a circuit state; it does not make every field contact circuit electrically equivalent. Check the excitation source, common wiring, terminal assignment, and Mark VIe configuration before energizing the replacement.
Related Products
- IS230SNCIH4A — Closely related SNCI contact-input variant; H4A should not be treated as electrically interchangeable with H6A without checking excitation requirements.
- IS230STCIH6A — Mark VIe discrete-input module using the STCI terminal-board family; closely related to SNCIH6A but should be matched by system configuration.
- IS230STCIH4A — Lower-voltage STCI discrete-input variant; not a direct substitute for the 125 VDC H6A configuration without verification.
- IS230SNIDH1A — Mark VIe isolated discrete-input module; different input architecture and application.
- IS230SNRLH2A — Mark VIe discrete-output module; used for outputs rather than contact-state acquisition.
- IS230SRLYH2A — Simplex discrete relay-output module; output function rather than input monitoring.
- IS230SNSCH2A — Mark VIe serial communication module; unrelated to contact input acquisition.
- IS230SNHRH2A — HART analog I/O module; used for analog/HART signals rather than discrete contacts.
Procurement Note
For a GE IS230SNCIH6A replacement, specify the complete catalog number and verify the installed terminal arrangement, I/O pack identification, field excitation voltage, and Mark VIe configuration.
A supplier description calling this part a “6-channel input/6-relay module,” generic Ethernet module, or analog I/O board should be treated cautiously. Those descriptions conflict with the stronger identification of the H6A as a 24-point, 125 VDC Simplex contact-input assembly.
For used or surplus hardware, check the I/O pack label as well as the terminal assembly. Mark VIe I/O packs carry their own hardware catalog, revision, serial, and firmware identification, so matching only the external IS230 part number may not be enough for a controlled replacement.
