Description
- Model: 9907-167 (505 Digital Governor)
- Brand: Woodward (USA)
- Series: 505 / 505E Controller Series
- Core Function: Configurable steam turbine control for speed and load
- Product Type: Digital Governor / Controller
- Key Specs: 24 V DC Power | Integrated Operator Interface | PID Control
- Power Input: 18–32 V DC (24 V DC Nominal)
- Operator Interface: Integrated 4-line LCD display and sealed membrane keypad
- Analog Inputs: 4 Configurable (4–20 mA)
- Analog Outputs: 2 Configurable (4–20 mA) for actuator drivers
- Discrete Inputs: 8 Configurable Contact Inputs
- Relay Outputs: 8 Configurable (Form C contacts)
- Communication: Dual Modbus RS-232/422/485 ports
- Speed Sensing: 2 MPU (Magnetic Pickup) or Proximity probe inputs
- Enclosure: NEMA 4X (When bulkhead mounted)
- Operating Temp: -25 to +65 °C
WOODWARD 9907-167
Application Scenarios & Pain Points
If you work with steam turbines, you know the Woodward 9907-167 is the industry workhorse. It’s designed to handle everything from simple generator drives to complex mechanical drives like feed water pumps or compressors. In my experience, the biggest “project killer” with these governors is an aging display or a keypad that stops responding due to chemical exposure in the plant. When the operator can’t manually override or see the speed bias, the turbine becomes a black box. Having a spare 9907-167 isn’t just about hardware failure; it’s about maintaining the ability to tune and monitor your prime mover during critical startups.
Typical Application Scenarios:
- Industrial Power Generation: Controlling steam turbines in sugar mills, paper mills, and refineries.
- Mechanical Drives: Precision speed control for large fans or pumps in petrochemical plants.
- Generator Sets: Isochronous load sharing and droop control for grid-connected units.
- District Heating: Managing steam flow and extraction for municipal heating systems.
Case Study: The “Blind” Startup
Background: A biomass power plant in Southeast Asia was attempting to restart after a planned outage.
Problem: The existing 505 governor’s LCD had “sun-baked” and was completely unreadable. The engineers couldn’t verify the “Overspeed Test” parameters or see if the governor was in a “Start Lockout” state. Without visual feedback, the safety protocol prohibited the steam roll.
Solution: We supplied a 9907-167 from our newplcdcs inventory. Since this model features a user-friendly configuration menu, the customer was able to port their existing settings over quickly.
Result: The new unit was installed and commissioned within 24 hours. The plant resumed operations, avoiding an additional $40,000 per day in lost power export revenue.
WOODWARD 9907-167
Troubleshooting Quick Reference
| Symptom | Possible Cause | Relevant to this Module? | Quick Check | Action |
| Screen is Blank | No Power / Internal Fuse | ✅ High | Measure 24V at terminals 1 & 2 | Check power supply/fuse |
| “Speed Fail” Alarm | MPU Signal Loss | ⚠️ Medium | Check MPU resistance (90–300Ω) | Adjust MPU gap or replace |
| Keypad Unresponsive | Membrane Damage | ✅ High | Try Modbus remote control | Replace 9907-167 unit |
| Actuator Not Moving | I/O Driver Failure | ✅ High | Measure 4-20mA at Actuator Out | Check wiring; replace unit if 0mA |
| CPU Fault LED | Internal Watchdog | ✅ High | Cycle power to reset | If fault returns, board is dead |
WOODWARD 9907-167
Technical “Pro-Tips” (Avoiding Common Pitfalls)
Working with the 9907-167 requires a “systems” mindset. Here is what I’ve learned from years of commissioning:
- The “Boot” Sequence: When you first power up a new unit, it enters “Configure” mode. Don’t just start clicking. You must have your turbine’s specific PID parameters (Proportional, Integral, Derivative) and speed setpoints ready. If you skip a step, the governor might “Trip” on startup because it hasn’t seen a valid speed range.
- MPU Shielding: I’ve seen turbines hunt for speed because the Magnetic Pickup (MPU) cable wasn’t shielded properly. The 9907-167 is sensitive to noise. Always ground the shield at the governor end only to avoid ground loops.
- Password Protection: If you’re replacing a unit, check if the old one had a service password. If you don’t have the original code, you can’t see the tuned values.
❗ Warning: Before you disconnect the old governor, use a Modbus tool or the front panel (if working) to write down every single setpoint. There is no “auto-magic” transfer of settings between old and new hardware.
Other Woodward Models in Our Inventory:
- Woodward 9907-162
- Woodward 9907-164
- Woodward 2301A (9905-020)
- Woodward 8237-159
- Woodward 723PLUS
- Woodward 5466-316
- Woodward 8440-1706
- Woodward 9907-838
