Description
Core Product Summary (Brand / Model / Key Attributes)
The Woodward SMM40 is a permanent-magnet synchronizing (speed adjusting) motor used for remote speed-setting of Woodward UG, PSG, and SG governors. Manufactured by Sawamura Denki Kogyo for Woodward Governor (Japan) Ltd., it provides precise electromechanical adjustment of the governor speed reference from a remote control station or switchboard.
The motor operates on a nominal 24 V DC supply (versions with internal rectifiers accept 110 V or 220 V AC). It delivers low-speed, high-torque output (typical safe torque 0.2 N·m) at rated speeds such as 2 rpm or 4 rpm, depending on the specific part number. The housing is rated IP44. The SMM40 is designed as a direct replacement for earlier Woodward speed-setting motors (S40, MM40, MM4A).
Key Technical Specifications
| Parameter | Value |
|---|---|
| Product type | Permanent-magnet synchronizing / speed adjusting motor |
| Manufacturer | Woodward (Sawamura Denki Kogyo) |
| Typical part numbers | 1766-523, 1766-541 and related 1766-series variants |
| Supply voltage | Nominal 24 V DC (AC versions with rectifiers for 110 V / 220 V) |
| Current | Approx. 0.15 A (24 V DC versions) |
| Rated speed | Commonly 2 rpm or 4 rpm (variant-dependent) |
| Safe torque | 0.2 N·m |
| Protection | IP44 |
| Function | Remote speed-setting of UG, PSG, and SG governors |
| Interchangeability | Direct replacement for S40, MM40, MM4A motors |
Detailed Product Overview
The Woodward SMM40 is a compact permanent-magnet motor specifically engineered to provide remote speed adjustment for Woodward mechanical and hydraulic governors of the UG, PSG, and SG families. It is mounted on the governor and mechanically coupled to the speed-setting mechanism, allowing an operator at a remote switchboard or control panel to raise or lower the engine or turbine speed reference without manual intervention at the governor itself.
Power is supplied at a nominal 24 V DC. Models fitted with internal rectifiers and a potentiometer can operate from 110 V or 220 V AC supplies, enabling flexible integration into different shipboard or industrial power systems. The motor produces a controlled, low rotational speed (typically 2 rpm or 4 rpm according to the specific variant) and a safe torque of 0.2 N·m, sufficient to drive the governor’s speed-setting linkage without overload.
The enclosure is rated IP44, providing protection against solid objects larger than 1 mm and against water splashes. This makes the unit suitable for installation in engine rooms and control spaces where moderate environmental protection is required. The SMM40 is documented as directly interchangeable with earlier Woodward permanent-magnet speed-setting motors (S40, MM40, MM4A), simplifying maintenance and upgrade of existing governor installations.
Correct selection requires matching the part number (e.g., 1766-523 for a 24 V DC, 2 rpm version or 1766-541 for a 4 rpm version) to the governor model and the available supply voltage. When used with appropriate motor-control circuitry, the effective speed range can be adjusted within defined limits. Proper mechanical coupling, electrical polarity, and verification that the governor’s manual speed-setting mechanism is free are essential for reliable operation.
Engineering Selection Highlights
- Exact model for remote speed setting of Woodward UG, PSG, and SG governors; not a general-purpose motor.
- Nominal 24 V DC operation (AC rectifier versions available) matches common control-power supplies.
- Low rated speeds (commonly 2 rpm or 4 rpm) and 0.2 N·m safe torque provide controlled, overload-safe actuation of the governor speed-setting mechanism.
- IP44 housing suitable for typical engine-room and control-cabinet environments.
- Direct mechanical and functional interchangeability with earlier S40 / MM40 / MM4A motors simplifies replacement.
- Part-number variants (e.g., 1766-523, 1766-541) define voltage, speed, and interface details; confirm against the governor nameplate and system documentation.
SMM40
System Compatibility & Integration Requirements
| Item / Dependency | Verified Compatibility or Requirement | Practical Note |
|---|---|---|
| Host governors | Woodward UG, PSG, and SG series | Mechanical coupling to the speed-setting mechanism required |
| Supply | Nominal 24 V DC (or 110/220 V AC with rectifier versions) | Match part number to available supply |
| Mechanical interface | Governor speed-setting linkage | Verify free movement of the manual speed-setting gear train |
| Electrical interface | Control wiring for raise/lower commands | Observe polarity and any potentiometer settings for AC models |
| Environmental | IP44 | Suitable for splash and dust protection in industrial/marine spaces |
Dimensions, Mounting & Connection Notes
The SMM40 is a compact, self-contained motor assembly with an IP44 housing. It mounts directly to the governor speed-setting mechanism. Electrical connections are made according to the specific part-number variant (24 V DC or AC with rectifier). Exact outline dimensions and weight vary by revision; typical units are lightweight and designed for direct governor mounting. Always confirm mechanical fit and electrical ratings against the motor nameplate and the applicable Woodward manual (e.g., Manual 03026) before installation.
FAQ
What is the Woodward SMM40?
It is a permanent-magnet synchronizing (speed adjusting) motor used for remote speed-setting of Woodward UG, PSG, and SG governors.
What supply voltage does it use?
Nominal 24 V DC. Versions with internal rectifiers accept 110 V or 220 V AC supplies.
What is the typical torque rating?
Safe torque is 0.2 N·m.
Which earlier motors does the SMM40 replace?
It is directly interchangeable with the earlier S40, MM40, and MM4A speed-setting motors.
What protection rating does the housing have?
.
How is the motor identified?
By the type designation SMM40 together with the specific Woodward/Sawamura part number (commonly in the 1766-series) shown on the nameplate.
Start Chat
