Category: Woodward

Stop/Ratio Valve Operation The Gas Stop/Ratio Valve actuator is controlled by an electronic servo-control system (not included), which compares the demanded and actual valve positions. The control system modulates the input current signal to the electrohydraulic servo valve to minimize the positioning system error. See Figure 1-2 for a functional schematic of the single acting actuator. Hydraulic oil enters the actuator via a removable element filter with integral high P indicator and is directed to a four way, electrohydraulic servo valve used in a three-way configuration. The PC1 control pressure output from the servo valve is directed to the top of the hydraulic piston. When the force exerted by the hydraulic pressure exceeds the force of the opposing loading springs, the output piston extends, rotating the valve in the opening direction. A trip relay valve assembly is interposed between the electrohydraulic servo control valve and the servo output stage. Loss or reduction of the externally supplied trip signal pressure causes the trip relay valve to shift position. This connects the upper cavity of the actuator piston to the hydraulic drain. The force supplied by the return springs pushes the actuation rod up, rotating the valve to the closed position. Two redundant LVDT position feedback transducers are also mounted within each actuator. An optional third LVDT is available on the 6” and 8” stop/ratio actuators only. The LVDT sensor cores and support rods are connected to the main actuator output rod by a coupling arrangement guided on a bushing. This guide bushing maintains LVDT alignment to minimize core damage due to sliding wear and the associated loss of sensing accuracy.

Optimum control of the gas turbine requires that the actuator and valve accurately and quickly track the

demand signals transmitted by the control. The stop/ratio valve has been designed to provide output

forces that exceed the opening and closing requirements with some margin. The additional margin helps

ensure that the system moves rapidly even under service conditions where the valve has been

contaminated or worn. The hydraulic trip relay valve has been selected to provide high operating force

margins, high flow capacity, and to ensure the desired closure rate of the valve under trip conditions.

By using a long actuation rod between the hydraulic cylinder and the valve lever arm, the side-loading

forces on the actuator shaft and seals are greatly reduced, decreasing the wear between sliding parts,

and increasing the useful service life of the system. The ample distance between the wetted heavy-duty

linear slide rings within the stop/ratio valve accommodates any remaining side load. These provisions

provide extended service life even in severe service conditions.

The governors are available with either a cast-iron case or a die-cast aluminum case.

Speed droop is required for stable governor operation. Droop is factory set, but internally adjustable.

Two means of speed setting are available. Screw speed setting is standard. Lever speed setting is

optional and provided by a serrated shaft assembly extending from both sides of the cover.

Governor drive shaft rotation for both governors is single direction only. In both the cast iron and the die

cast aluminum governors, rotation can be changed in the field. In the cast iron governor, it must be

changed internally, and in the die-cast aluminum governor, it can be changed externally by removing

four screws and rotating the pump housing 180 degrees (see Chapter 2).

Governor maintenance is minimal due to few moving parts, weatherproof design, and self-contained oil

supply. The governor drive shaft operates a gerotor oil pump. Internal oil pump pressure is regulated by

a relief valve/accumulator. The oil sight gauge installed on each side of the governor case makes oil

condition and oil-level checking simple.

Description  The Woodward TG-13/TG-17 and TG611-13/TG611-17 are mechanical-hydraulic speed droop governors for controlling steam turbines—applications where isochronous (constant-speed) operation is not required. The TG-13/TG-17 and TG611-13/TG611-17 governors have a full 40 degrees of maximum terminal-shaft travel. Recommended travel from the no load to the full load position is 2/3 of full governor travel. See Figure 1-1 for a graphic representation of maximum work capacity for the governors and related governor terminal shaft travel information. The TG-13/TG611-13 governor operates with 1034 kPa (150 psi) internal oil pressure, and the TG 17/TG611-17 operates with 1379 kPa (200 psi) internal oil pressure. Either governor is set to the speed range specified by the customer at time of order. The high-speed governor (4000 to 6000 rpm) may require a heat exchanger in some applications (see end of Chapter 2, “When is a Heat Exchanger Necessary?”). Both governors are capable of controlling at lower-than specified speed range with some loss of output torque and performance. The governor should not be run at a speed greater than the range specified because of heat rise and component wear issues.

Features The actuator output is an ISO 9409 flange. This allows for easy mounting of levers to simplify replacement. The orientation of the output flange relative to the bracket base is the same for each actuator. Additionally, the actuators are equipped with break-away stops that prevent the actuator from exceeding the maximum output travel range during setup. An output position indicator is standard. The EM-80 and EM-300 systems include a mounting bracket with hole pattern. The bracket design ensures that stresses in the actuator are reduced to a minimum. Actuator specifications and performance are based on a system including bracket. The actuators are equipped with a flying-lead position-sensor cable (including connector). A position sensor cable connecting the actuator and the driver is available. This cable is similar for both the EM-80 and the EM-300. A single EM-driver is used for both the EM-80 and the EM-300. Only the software setup for each actuator system differs. Monitoring, alarm, and diagnostics are available. An EMI power filter is supplied to suppress emissions. Optional Features The EM-80 and EM-300 systems include a bracket for mounting on the engine or turbine. A standard mounting hole pattern is provided. Alternative patterns are available on request.

Applications The EM-80 and EM-300 are intended to be mounted on large diesel, gas, and gasoline engines, and on all types of turbines, to control the position of engine fuel racks, turbine fuel valves, turbine and turbocharger variable geometry, and to handle timing control. These systems are well suited for engines without a mechanical drive or hydraulic oil supply. Description The EM-80 and EM-300 are all-electric actuator systems that provide 40 degrees of actuator output rotation. Each system consists of a three-phase brushless ac motor which drives a high-precision planetary reduction gear box. A dedicated driver controls the actuator position and allows monitoring of most features. PC/Windows based software facilitates the system setup. The EM-80 and EM-300 are freely programmable to meet many customer requirements.  Fast slew times  Freely programmable  Brushless servomotor and resolver  Precision gearbox, high stiffness, low backlash  CE marking  Models with ABS, BV, and DNV certification  Cost effective solution

Description The WRZ Series Wireless Room Sensors are designed to sense room or zone temperature and transmit wireless temperature control data. Some models also sense and transmit relative humidity (RH). Several models include an onboard passive infrared (PIR) occupancy sensor that detects motion to determine if a space is occupied. This feature maximizes up to 30% energy savings in high-energy usage environments such as schools, dormitories, offices, and hospitals by adjusting the temperature of the space based on the occupancy status. In addition, the PIR occupancy sensor facilitates trending of floor space usage in these environments. In a ZFR1800 Series Wireless Field Bus System application, the sensors communicate with FAC26 Series, FEC16 Series, FEC26 Series, and VMA16 Series Controllers by means of the ZFR18xx Series Router. In wired field bus applications, the sensors communicate with a WRZ-7860 Wireless Receiver. The WRZ-7860 Receiver transfers data to the controller by means of the Sensor Actuator (SA) communication bus. In a typical application, one WRZ Series Sensor reports to one WRZ-7860 Receiver, but up to five WRZSeries Sensors can be associated with a single WRZ-7860 Receiver for multi-sensor averaging or high/low temperature selection. The WRZ Series Wireless Room Sensors include models with either a temperature setpoint dial or the setpoint adjustment pushbuttons and LCD that allows occupants to view the zone temperature, Relative Humidity (RH), and view and adjust the zone temperature setpoint. Some temperature and humidity models include a %RH pushbutton to toggle between temperature and RH on the display. These models also have the capability to set the desired default display to either temperature or RH. Some models also include a °F/°C button, which provides a choice between degrees Fahrenheit (F) and degrees Celsius (C).

The EM-80 and EM-300 actuators have different position-sensing systems. Both

systems use the same hollow shaft resolver, producing a sine and cosine wave

output with an overall accuracy of 12 arc-minutes. This resolver is mounted at the

rear of the motor and looks at the relative position of the motor shaft.

The EM-80 uses only the resolver since the 1:7 gear ratio within the gearbox

allows full stroke of the actuator output flange with less than one full revolution of

the motor shaft.

The EM-300 has a 1:20 gearbox ratio to achieve the required torque output.

Because of this, the motor shaft rotates more than one full revolution to achieve

full stroke. To ensure proper position indication over the full range, a 10-turn

potentiometer is added behind the resolver to supply a coarse position signal

from which the correct rotor revolution is deduced. The same resolver as used on

the EM-80 gives the accurate position within that revolution.

EM-80/-300 System Description The EM-80/-300 system consists of an actuator, a driver, an AC line filter (required for marine TN/TT only), and interconnection cables. The EM-80 and EM-300 are all-electric actuator systems that provide a nominal 40° of actuator output rotation. Each system consists of a three-phase brushless ac motor which drives a high-precision planetary reduction gear box. A dedicated driver controls the actuator position. Actuator The actuator is available in two versions, offering two work output levels, EM-80 and EM-300. Both versions use the same three-phase brushless AC motor. The difference in output is achieved by the use of two different gearboxes. The EM-80 uses a single-stage planetary 1:7 gear ratio, while the EM-300 uses a two-stage planetary 1:20 gear ratio. The motor–gearbox combination comes assembled on a mounting bracket with a fixed hole pattern. Although the EM-300 is longer than the EM-80. both use the same mounting hole pattern, allowing the actuators to be interchangeable. The output flange provides an easy mounting surface for a variety of lever configurations, and is equipped with a rugged pointer and scale for quick output position reference while working on the prime mover. A breakaway extension and two stop pins form a simple means of detecting whether the actuator has been driven outside its operating boundaries.

Introduction This manual covers components of the EM-80/-300 Actuator System and does not include operating instructions for the prime mover or the driven devices or processes. For information about other Woodward products used in conjunction with the EM-80/-300. please refer to the specific Woodward documentation supplied with each product. For specific operating information such as start-up, shutdown, and the prime mover’s response to signals from the Woodward control, refer to the prime mover manufacturer’s manual. Description of Components The EM-80/-300 system provides an all-electric actuation system for various prime mover control applications. The system is intended for use on large diesel, gas, and gasoline engines, and on all types of turbines, to control the position of the engine fuel racks, turbine fuel racks, turbine and turbocharger variable geometry, and to perform timing control. The EM Driver controls the EM-80/-300 Actuator position proportional to a position demand signal received from a controlling device. The EM-80/-300 Actuator consists of a high-performance three-phase brushless ac motor that drives a precision planetary gearbox.