Woodward 3171A, Руководство по эксплуатации продукта, Страница: 40 / 47

EM35MR1/3171A Gas Valve Manual 26731
30 Woodward
EM35MR1/3171A Specifications
The EM35MR1 electric actuator was designed for the positioning of Woodward gas and
liquid valves equipped with resolver feedback. The actuator requires a final driver for
driving the motor and for closed-loop control.
The EM35MR1 actuator uses a brushless dc motor with a 137:1 reducing planetary
gearhead. The motor is designed with Samarium Cobalt permanent magnets bonded to
the rotor element, and all stator windings are completely sealed. Rotor position sensing is
performed by the resolver unit integral with the motor. This inductive device requires
excitation and demodulation within the electronic motor controller.
Mechanical
Output shaft rotation 45° (Rotation limited by valve stops)
Actuator/valve coupling Direct Coupling
Torque constant 1.8 N

m/A (16 lb-in/A)
Continuous output torque ±25 N

m (±220 lb-in) maximum
Peak output torque ±62 N

m (±552 lb-in) minimum
Clutch breakaway torque ±68 N

m (±600 lb-in)
Valve gas connection 1" 600# ANSI B16.5 (25 mm, 2669 N)
Gas flow 11 to 9070 kg/h (25 to 20 000 pph) natural gas
Gas pressure 0 to 6205 kPa (0 to 900 psia)
Electrical
Motor Voltage 28 Vdc nominal, 18–32 Vdc operating
Motor Current 15 A continuous
37 A peak current for 50 ms
System Accuracy
Using 485 or CAN for control:
Accuracy: ± 6 arc min RSS (Root Sum Squared)
Using 4–20 mA for control:
Initial Accuracy: ± 0.22°
Accuracy Over Temperature: ± 1.372°
4–20 mA Position Readback:
Initial Accuracy: ± 0.24°
Accuracy Over Temperature: ± 0.49°
System Performance
Slew Time Performance—Less than 100 ms to open and close the valve at a line voltage
of 24 Vdc. This slew rate shall be measured using the speed achieved between the 10%
and 90% points. The rated stroke of the 3171A Gas Valve is 45°.
System bandwidth is nominally greater than 31.4 rad/s (5.0 Hz). The frequency response
mimics a 2-pole linear system, with the bandwidth corresponding to –6 dB gain. The
damping factor is set to 1.
Equivalent dead time does not exceed 40 ms, which includes all effects such as the
communications, processing time, mechanical times, etc.
Environmental
Ambient Temperature
Valve, Actuator, & Resolver: –40 to +93 °C (–40 to +200 °F)
Fuel Temperature: –40 to +149 °C (–40 to +300 °F)
Vibration:
US MIL-STD-810C Method 514.2, Category b.1,
Table 514.2-II, Figure 514.2 curve j (5 g)
Shock: US MIL-STD-810C, Method 516.2, Figure 516.2-1, 20g 11ms sawtooth