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Phone: +86 16626708626Description
Key Technical Specifications
- Function: Speed/load PID control for single or split-range actuator steam turbines, turbogenerators, and turboexpanders (not extraction — that’s the separate 505E line)
- Power Input: 18-32 Vdc (LVDC variant), 6.25 A internal fuse, 77 VA maximum draw
- Power Supply Holdup Time: 14 ms (worst case)
- Speed Sensor Inputs: 2, jumper-configurable for magnetic pickup (MPU) or proximity probe
- Analog Inputs: 6 programmable 4-20 mA inputs, 200 Ω input impedance
- Contact Inputs: 16 total (4 dedicated: shutdown, reset, raise/lower speed setpoint; 12 programmable)
- Actuator Outputs: 2, configurable for 4-20 mA (max 360 Ω loop impedance) or 20-160 mA Woodward-type actuators (max 45 Ω)
- Analog Outputs: 6, 4-20 mA, drive into max 600 Ω
- Relay Outputs: 8 Form-C contacts (2 dedicated: alarm, shutdown; 6 programmable)
- Communications: 2 Modbus ports (RS-232/RS-422/RS-485, ASCII or RTU), 1 PC configuration port
- Internal 24V Transducer Supply: 24 Vdc ±10%, 200 mA max per channel, two channels
- Weight: Approx. 4 kg (9 lb), standard flush-mount package
- Operating Temperature: −25 to +65°C ambient (standard enclosure)
- Certifications: UL/CUL listed (UL file E156028) for Class I, Division 2, Groups A, B, C, D; compliant with EN60079-15 for European Zone 2, Group II
Product Introduction
The Woodward 9907-164 is the low-voltage DC variant of the 505 Digital Governor, a microprocessor-based control built for single or split-range actuator steam turbines, turbogenerators, and turboexpander modules. It runs on 18-32 Vdc input power and includes a full operator control panel — a two-line, 24-character display with a 30-key pad — built into the front of the unit, so no separate HMI is required.
The 505 handles speed control, frequency control, and unit load (droop) control depending on generator breaker states, with 16 contact inputs, 6 programmable analog inputs, and dual Modbus ports for tying into a plant DCS. Field-programmable configuration means one hardware design covers a wide range of turbine applications — reducing the guesswork when replacing a unit in an existing installation, as long as the power class (LVDC vs. AC/DC vs. HVAC) matches.
9907-164
9907-164
Troubleshooting Quick Reference
| Symptom | Possible Cause | Relevance to this Part | Quick Check Method | Recommendation |
|---|---|---|---|---|
| Unit won’t power up at all | Input power out of 18-32 Vdc range or internal fuse blown | ✅ High | Measure input voltage at power terminals; check internal fuse | Confirm power source before condemning the unit |
| “Stuck in Critical” alarm during startup | Critical speed rate set too aggressive for the turbine’s actual acceleration | ❌ Low | Review Critical Speed Rate setting against turbine capability | Adjust programming before assuming hardware fault |
| No speed signal detected / shutdown on start | MPU/proximity probe wiring or jumper misconfiguration | ✅ High | Verify jumper settings match probe type (MPU vs. proximity) per Table 2-1 | Check jumpers before replacing the governor |
| Actuator not responding correctly | Actuator output configured for wrong drive current type (4-20mA vs. 20-160mA) | ✅ High | Verify actuator output configuration in Program Mode | Reconfigure before assuming actuator or unit failure |
| Unstable speed control after paralleling to grid | Droop percentage misconfigured or KW input signal failed | ⚠️ Medium | Check KW Droop setting and watt transducer signal | Confirm droop configuration matches your paralleling scheme |
If a fault doesn’t clear with basic checks, send your jumper configuration, program settings, and alarm history to technical support before swapping the unit — a lot of “bad governor” calls trace back to jumper or program mode settings on these boards.
Frequently Asked Questions (FAQ)
Is the 9907-164 the same as a 505E?
No — this is the standard 505, for single or split-range actuator turbines. The 505E, which handles extraction and extraction/admission turbines, is a separate product line covered under its own manual and part numbers. Don’t assume interchangeability based on similar reseller descriptions.
Can I substitute this for a 9907-162 or 9907-163?
Only if your installation’s power source matches. The 9907-164 is the LVDC variant (18-32 Vdc). The 9907-162 is HVAC (180-264 Vac) and the 9907-163 is AC/DC (88-132 Vac or 90-150 Vdc). These aren’t interchangeable without rewiring your power source.
Will my existing configuration transfer to a replacement unit?
No — configuration is programmed through the front-panel keypad on each individual unit; it’s not stored externally or transferable via cable. Budget time for full reprogramming and jumper verification during commissioning, and keep your original program settings documented before removing the old unit.
Why is this priced below a factory-new quote?
This is a legacy part number, and most available stock is surplus or reconditioned. Ask your supplier what testing was performed and whether the polyacrylate conformal coating revision (for sulfur-resistant environments) is present on the specific unit you’re buying — check for a “SULFUR RESISTANT CONFORMAL COATED” label if that matters for your site.
Do I need both an MPU and a proximity probe, or just one?
The 505 supports one or two speed inputs; using two increases reliability, but one is sufficient if configured correctly. If using two, both must sense from the same gear — mixing an MPU and proximity probe on different gears isn’t supported.
Is this unit rated for hazardous locations?
Yes, if the enclosure carries the certification label — UL/CUL listed for Class I, Division 2, Groups A, B, C, D, and compliant with EN60079-15 for European Zone 2. Confirm the specific unit you’re buying carries this certification marking; the listing applies only to units bearing it.
