The Okuma 1911-2861 is a specialized graphic card circuit board module designed for integration into Okuma CNC machine tool control systems. This board provides the graphical output capabilities necessary to drive the operator display screen, rendering real-time machine status, part programs, tool path simulations, and diagnostic information. As part of Okuma’s proprietary PLC-based control architecture, the 1911-2861 works in conjunction with the main CPU board and I/O modules to deliver a comprehensive user interface for machine operators and maintenance personnel. The board is built to withstand the electrical noise, temperature variations, and vibration levels typical of a machine shop environment.
In an Okuma CNC system, the graphic card module receives video data from the main CNC processor via a dedicated internal bus. It then converts this data into a standard video signal, typically VGA or a proprietary analog format, which is transmitted to the operator’s CRT or LCD monitor. The board may incorporate its own video RAM and a graphics processor capable of handling 2D and basic 3D rendering for tool path display and part geometry visualization. This offloads graphics-intensive tasks from the main processor, improving overall system responsiveness. The 1911-2861 also likely supports overlay functions, combining text, alarm messages, and graphic elements onto the same display area.

The circuit board is constructed on a high-quality FR-4 substrate with UL 94V-0 flammability rating. Components are selected for extended temperature range operation, typically from 0 to 60 degrees Celsius. The board includes one or more video output connectors, often DB-15 type for analog VGA or BNC for composite video. Power is derived from the backplane or a dedicated power connector, operating on +5 V DC and possibly +12 V DC rails. The board features memory chips for frame buffering and may contain an EEPROM storing firmware and configuration data specific to the machine model. Jumper settings or DIP switches may be present to configure video timing, resolution, and sync polarity for compatibility with different display monitors.
When the graphic card malfunctions, typical symptoms include a blank screen, distorted images, rolling display, or flickering. The 1911-2861 includes onboard diagnostic LEDs that indicate power presence and video signal generation status. Some revisions also include a test pattern generator that can be activated via jumpers to verify the monitor’s operation independently of the CNC processor. In an Okuma machine, the PLC diagnostic menu can check the status of the graphic card by polling a specific memory address. If the card is missing or unresponsive, the control may still boot in a text-only mode, allowing limited operation for troubleshooting purposes. Replacement of the board should be performed with the machine powered off, and careful attention must be paid to cable orientation and seating of the board into its slot.
The 1911-2861 graphic card is designed for specific Okuma machine models and control versions. Compatibility depends on the revision level printed on the board. When replacing, the exact part number and revision should be matched to ensure correct video timing and resolution support. Some later Okuma controls use digital flat panel interfaces, but this module is intended for legacy analog monitors. If the original monitor has been replaced with a modern LCD, a signal converter may be required. Okuma’s documentation includes detailed specifications for the video output signals, including horizontal frequency typically 31.5 kHz for VGA and vertical refresh rate of 60 Hz. Installation involves removing the old board, verifying that the new board’s jumpers match the old one’s settings, and carefully reseating all cables.



