Woodward 9907-018 | Steam Turbine Governor, New Original

Description

Note: Many products are not yet listed. Please contact us for more product information. Our supply channels are constantly expanding, and we currently have 20 stable shared supply channels. Please confirm the model, product, price, and all other necessary information with customer service before placing an order. We offer new, refurbished, and used products, and prices are adjusted according to the year of the item you require.

3. Key Technical Specifications

Confirm each line against the OEM datasheet and the label on your existing unit before ordering. I/O count and communication options vary across the 505 governor family.

4. Product Introduction

The Woodward 9907-018 is a 505 Digital Governor — a steam turbine controller that manages speed, load, and start-up sequencing. It takes speed signals from magnetic pickups, executes the governing algorithm, and drives the actuator through a 4–20mA output. It is the device that holds turbine speed at setpoint and manages the load sharing when the generator is paralleled to the grid.

The engineering value is the integrated start-up sequencing. Older mechanical governors required a separate sequencer or an operator to manually walk the turbine through the start-up curve. The 505 governor holds the ramp rates, the soak times, and the critical speed avoidance in one package. In my experience, that is what lets a plant start a steam turbine with a single command instead of a checklist.

Two things decide whether a swap works. First, the configuration file. The governor’s tuning, start-up curve, and I/O assignment live in the controller, not in a separate module. Pull the configuration from the old unit before you remove it. Second, the firmware revision. A newer governor firmware may not accept an older configuration file without conversion.

9907-018

9907-018

9907-018

5. Application Scenarios & Field Experience

Part 1 – Narrative Paragraph

The failure that hurts most on a steam turbine governor is a speed control loop that becomes unstable under load. The turbine runs at no load, the governor holds speed, and then the generator is paralleled and the speed starts to oscillate. I have seen that traced to a magnetic pickup that had lost a tooth or a gap that had drifted, not a failed governor. The governor was doing its job with a degraded speed signal. Before you replace a 505 governor, check the pickup gap, the pickup resistance, and the cable shielding. A new governor with the same degraded signal will behave the same way.

Part 2 – Numbered List (Application Scenarios)

1. Power Generation – Steam Turbine Speed Control – The governor holds turbine speed at synchronous setpoint during start-up and manages load sharing when the generator is paralleled. The magnetic pickup inputs provide the speed feedback for the control loop.
2. Industrial Plants – Mechanical Drive Steam Turbines – Used to control steam turbines that drive compressors, pumps, or fans. The 4–20mA output drives the governor valve actuator, and the discrete inputs handle start, stop, and trip commands.
3. Cogeneration – Extraction Steam Turbine Control – The governor manages both speed and extraction pressure on a cogeneration turbine. The load control loop balances the electrical output against the steam extraction demand.
4. Waste-to-Energy – Turbine Start-Up Sequencing – The governor holds the ramp rates and soak times during a cold start. The critical speed avoidance logic protects the turbine from vibration damage during the run-up.

Part 3 – Short Field Story

A waste-to-energy plant had a steam turbine that would not hold synchronous speed after the generator was paralleled. The crew had replaced the governor and the actuator and the problem persisted. We asked them to check the magnetic pickup signal with a scope. The signal was clean at low speed but showed a drop-out at 3000 RPM — the pickup gap had drifted and the signal was marginal at the higher frequency. The plant reset the gap, and the governor held speed. The replacement governor had been a spare that was never needed.

6. Standard Operating Procedure (SOP) for Quality Control

• Visual & Origin Inspection – We verify the Woodward marking, the 9907-018 model string, and the date code. We inspect the connectors and the front-panel display for damage. A unit with a cracked display or damaged connector is rejected.
• Revision and Configuration Documentation – We read and photograph the full model string, the firmware revision, and the configuration summary. We extract and archive any existing configuration file before shipping. That record ships with the unit so you can compare it against the unit you are replacing.
• Power-Up Self-Test – The governor is powered at rated voltage. We verify it completes its boot sequence, the display initializes, and no fault code is latched.
• Speed Input Verification – We inject a calibrated frequency signal into each magnetic pickup input and verify the governor’s measured speed tracks the reference. We test across the operating speed range.
• Actuator Output Verification – We command the actuator output to 4mA, 12mA, and 20mA into a calibrated load and verify the output matches the command. Accuracy must stay within the OEM specification.
• Discrete I/O Verification – We exercise each discrete input and output and verify the governor responds correctly. We test the trip input and the trip output as a pair.
• Communication Test – We connect to the serial port and verify the governor responds to configuration queries. We record the protocol settings so you can compare them against your plant’s setup.
• ESD-Safe Packaging – The unit is wrapped in anti-static film, seated in a foam insert with the connectors protected, and packed in a double-wall carton with static warning labels.

7. Frequently Asked Questions (FAQ)

Q1: Can I replace a 9907-014 with this 9907-018?

A: Not without checking the configuration. The 505 governor family has multiple part numbers that differ in I/O count, communication options, and firmware revision. A 9907-018 may have more or fewer channels than the unit you are replacing. Compare the full model string and the I/O list on both units before ordering. If you send us a photo of the label and the terminal assignment, we can confirm the match.

Q2: Will my existing configuration file load into this governor?

A: Only if the firmware revision matches or is compatible. The configuration is tied to the governor’s firmware version. If the replacement has a newer firmware revision, you may need to convert the file or re-enter the settings manually. Pull your existing configuration before you remove the old unit — that file is your recovery path.

Q3: What is the warranty on this governor?

A: We offer a 12-month warranty from the ship date. It covers processor failure, display failure, speed input failure, actuator output failure, and communication port failure under normal operating conditions. It does not cover damage from incorrect supply voltage, reversed field wiring, or ESD damage from handling without a wrist strap. Every unit is bench tested at rated voltage before it ships.

Q4: Do you have this exact model in stock?

A: Woodward governor inventory moves and varies by revision. Confirm availability before you plan an outage. If we do not have the exact variant you need, we will tell you what we do have and whether a different build would suit your turbine. Do not assume any 505 governor will drop in — the I/O count and firmware revision matter.

Q5: Any installation pitfalls I should watch for?

A: Four. First, verify the magnetic pickup gap and the pickup resistance before you install the governor. A degraded speed signal will cause the new governor to behave like the old one. Second, verify the actuator output wiring and the valve positioner calibration before you power up. Third, back up the configuration file from the old governor before you remove it. Fourth, after the swap, verify the governor holds speed at no load and under load before you return the turbine to service. A governor that powers up is not necessarily controlling correctly.