The IS215VCMIH2CA is a high‑performance VME Bus Master Controller (VCMI) board from GE, designed for use in Mark VI turbine control systems. Fully designated as IS215VCMIH2CA, this board serves as the communication interface between the controller and I/O boards, and as the interface to the system control network known as IONet. The IS215VCMIH2CA is also the VME bus master in control and I/O racks, managing board IDs and terminal board associations for all devices in the rack. This version features three IONet ports (H2 variant), supporting triple modular redundant (TMR) configurations and remote I/O racks.
The IS215VCMIH2CA is a 6U high VME board powered by a Texas Instruments TMS320C32 32‑bit digital signal processor (DSP). It provides dual‑port memory, SRAM, flash memory, and one RS‑232 serial port. The board monitors internal power supply buses (±12 V, ±15 V, ±28 V, +5 V) and external signals from the power distribution module (PDM). It is configurable via GE’s ToolboxST software.
The “CA” suffix indicates a specific factory configuration (e.g., conformal coating, extended temperature range, or particular revision). This product introduction provides a complete, SEO‑optimized specification for the IS215VCMIH2CA. All references use the full product designation to meet Google’s content uniqueness and keyword relevance standards.
Key Features of IS215VCMIH2CA
Triple IONet Ports: Three 10Base2 Ethernet ports (BNC connectors) for R, S, T channels in TMR systems
Powerful DSP: Texas Instruments TMS320C32 32‑bit processor
VME Bus Master: Controls VME backplane and manages board/terminal board IDs
Memory Resources: 32 Kbytes dual‑port RAM (32‑bit), 256k x 32 SRAM, 4096K x 8 flash (VCMIH_C variant)
RS‑232 Serial Port: 9600 baud for diagnostic and configuration access
Comprehensive Power Monitoring: Monitors +5 V, ±12 V, ±15 V, ±28 V buses with configurable alarm limits
External PDM Monitoring: Ground fault, over/under voltage on 125 V bus, two differential ±5 V analog inputs, digital inputs
Configurable via ToolboxST: System limits, power bus diagnostics, 125 V bus limits, logic inputs, analog input scaling
Support for Simplex and TMR: Frame rates: 10 ms (simplex), 40 ms (TMR), plus application‑dependent rates (20 ms, 80 ms)
Remote I/O Capable: Multiple I/O racks can be connected via IONet, each with its own VCMI board
Diagnostic Alarms: Over 60 fault conditions monitored, including power supply limits, communication failures, ID mismatches
Functional Description
The IS215VCMIH2CA is the communication hub in a Mark VI control system. It bridges the controller (e.g., UCCC or VME processor) with I/O boards via the VME backplane and with remote I/O racks via the IONet. The board’s three independent 10Base2 Ethernet ports (R, S, T) support TMR configurations, where each channel has its own dedicated IONet. Multiple I/O racks can be daisy‑chained on each IONet.
As VME bus master, the IS215VCMIH2CA handles all data transfers between the controller and I/O boards, and also reads identification (ID) chips from every VME board and its associated terminal board to verify correct system configuration.
The onboard TMS320C32 DSP executes real‑time communication and control tasks, managing the dual‑port memory (shared with the controller), SRAM for data buffering, and flash memory for firmware storage. The flash size on the IS215VCMIH2CA (H2C variant) is 4096K x 8, providing ample space for complex topologies.
The IS215VCMIH2CA also monitors critical power supplies and external signals. Alarms are generated when voltages exceed configurable limits, helping to prevent hardware damage or control malfunctions. The board can be configured via ToolboxST to enable/disable system limits, set voltage thresholds, define analog input scaling, and assign logic inputs.
System Configurations
Simplex – One IONet channel (but H2 version has three ports; only one may be used in simplex, or they can be used for separate networks). Frame rate: 10 ms.
TMR – Three independent IONets (R, S, T) with voting logic. Frame rate: 40 ms.
Remote I/O – I/O racks located away from the main control rack, each with its own VCMI, connected via IONet.
IONet and Bus Mastering
The IS215VCMIH2CA uses 10Base2 Ethernet (coaxial BNC) for IONet communication. This is a private, deterministic network dedicated to I/O data exchange. Each IONet supports multiple remote racks. The board automatically handles auto‑slot ID assignment and board/terminal board ID verification. If a mismatch is detected between the configuration (topology file) and the actual hardware, the board generates a fault (e.g., Fault 56: Topology File/Board ID Mismatch).
Diagnostics and Alarms
The IS215VCMIH2CA continuously monitors internal and external conditions and can report over 60 distinct fault conditions via ToolboxST. Key diagnostic categories include:
Power supply limits (P5, P15, N15, P12, N12, P28A‑E, N28) – Faults 32–42
125 V bus monitoring (over/under voltage, ground fault) – Faults 43–44
IONet communication failures – Faults 45–47, 59
VME bus errors – Faults 48, 60
Board ID / Auto Slot ID failures – Faults 17–24, 54–56
Firmware/hardware incompatibility – Faults 2–4, 24, 30–31
I/O board offline – Faults 68 (and 68‑xx for specific slots)
SRAM / configuration size exceeded – Faults 88–90
All alarms are logged and can be reset via ToolboxST. The board also monitors its own watchdog timer and can report if it is not armed.
Configuration Parameters
Using ToolboxST, the IS215VCMIH2CA can be configured with the following key parameters (partial list):
Parameter | Description | Typical Range |
System Limits | Enable/disable all system limits | Enable / Disable |
PS_Limit1 | Limits for P5, P15, N15 (%) | 0 to 10 |
PS_Limit2 | Limits for P12, N12, P28, N28 (%) | 0 to 10 |
PwrBusLimits | Enable/disable power bus diagnostics | Enable / Disable |
125vBusHlim | High limit for 125 V dc bus (volts) | 0 to 150 |
125vBusLlim | Low limit for 125 V dc bus (volts) | 0 to 150 |
P125vBusGlim | Low volts to ground limit for 125 V bus | 0 to 150 |
J3 Power Monitor | PDM connected status | Connected / Not connected |
Logic_In_1..12 | Enable/disable logic inputs | Used / Unused |
Input Type (analog) | Analog input type | Used / Unused |
Low_Input / Low_Value | Scaling for analog inputs | -10 to +10 V; engineering units |
The board also monitors spare analog inputs (Spare01, Spare02) from connector P3.
Installation and Replacement
Physical Installation
The IS215VCMIH2CA mounts in a 6U VME backplane (standard Mark VI rack). Before installation:
Ensure the rack is powered off.
Verify that the board’s jumpers (if any) are set according to the application (refer to Mark VI documentation; the VCMI typically has configurable jumpers – not detailed in this excerpt).
Slide the board into the appropriate slot (usually slot 1 or a designated VCMI slot) and secure with front panel screws.
Connect IONet cables (BNC) to the required ports (R, S, T). Use proper 10Base2 terminators if needed.
Connect the serial cable (RS‑232) to COM port for initial configuration if required.
Connect the PDM interface (J301) if monitoring of 125 V bus and external signals is needed.
Replacement Procedure
De‑energize the VME rack (follow lock‑out/tag‑out procedures).
Disconnect all cables (BNC, serial, J301) from the IS215VCMIH2CA.
Loosen the front panel screws and carefully pull the board from the backplane using ejector handles.
Insert the replacement IS215VCMIH2CA into the same slot, ensuring proper alignment with the backplane.
Push firmly to seat the board, then tighten the front panel screws.
Reconnect all cables.
Re‑apply power. The board will boot and read its firmware from flash.
Using ToolboxST, verify configuration parameters (system limits, power bus diagnostics, etc.) and download the topology file if changed.
Monitor diagnostic alarms to ensure no faults remain.
After replacement, check that all I/O boards are recognized and that IONet communication is restored.
Board Identification
The IS215VCMIH2CA is identified by its catalog number:
IS215 – product series
VCMI – VME Bus Master Controller
H2 – hardware version with three IONet ports (H1 has one port)
C – flash memory size (4096K x 8) and processor variant
A – suffix indicating specific factory configuration (e.g., conformal coating, revision)
Placing an Order
When ordering a replacement IS215VCMIH2CA, provide:
Contact your nearest GE Sales or Service Office, or an authorized GE representative.
Warranty
Refer to the GE Terms and Conditions brochure for warranty period and coverage. GE ensures backward compatibility of replacement boards; later versions may be substituted based on availability.
Why Choose IS215VCMIH2CA for Your Mark VI System?
The IS215VCMIH2CA is a proven, rugged VME bus master controller designed for the demanding environment of turbine control. Its triple IONet ports enable TMR architectures with high availability, while the powerful DSP ensures low‑latency data transfer between controllers and I/O. Key advantages include:
Triple redundant I/O networks for fault‑tolerant operation
Comprehensive power and signal monitoring – early warning of supply issues
Flexible configuration via ToolboxST with extensive alarm reporting
Support for remote I/O racks – scalable system design
Backward compatibility with existing Mark VI VCMI installations (check firmware version)
Industrial reliability – 6U VME form factor, wide temperature operation
