The Woodward 9907-1182, also cataloged as the 9907-1182 Digital Governor Controller, operates as a dedicated hardware component for speed and extraction control within 505 Digital Governor platforms.

Hardware Specifications

Actuator Loop Feedback & Speed Control Performance

The digital governor executes closed-loop speed control and extraction steam turbine positioning via 2 discrete actuator outputs and 6 programmable 4-20 mA analog channels. High-speed processor execution ensures rapid actuator loop feedback response to transient load fluctuations. Dynamic adjustments prevent turbine overspeed conditions, while harmonic distortion suppression and precise signal filtering preserve system stability across changing steam admission parameters.

Frequently Asked Questions

• Q: What cable specifications are required for the RS-485 Modbus RTU communication link?
• A: Communication lines require twisted-shielded pair conductors routed away from high-voltage AC cables, with 120 ohm termination resistors installed across the physical endpoints of the RS-485 bus.
• Q: How are the 6 programmable analog outputs wired for loop isolation?
• A: The 4-20 mA analog outputs provide internal loop drive powered by the unit; external wiring must connect to isolated receiver channels to prevent ground loop currents from skewing signal values.
• Q: What sealing measures preserve the IP67 enclosure integrity during panel mounting?
• A: All cable entry ports must utilize rated IP67 liquid-tight cable glands or conduit seals, and the front keypad gasket must sit flush against the enclosure mounting cutout.

Field Installation Guidelines

• Mount the controller vertically on a rigid structural surface to allow adequate thermal convection across the rear enclosure body.
• Terminate all signal cable shields at a single chassis ground lug to prevent ground loop noise on the 4-20 mA analog channels.
• Ensure 24 VDC supply wiring includes appropriate overcurrent circuit protection rated to handle the maximum 1 A operational draw.
• Keep sensor input lines and RS-485 communication runs physically separated from relay coil switching circuits and heavy inductive loads.