AUMA SA 6 - Actuators for Regulating Duty; Description of Regulating Duty

Description of Regulating Duty
Principle of Operation
Actuators for Regulating Duty
Auma actuators of type SAR are suitable for
Regulating duty / Modulating duty. SAR
actuator operates between two set bands in
closed loop and the motor is started, stopped
& reversed at short intervals to correct the
deviation from the set value. SAR actuators
differ from SA actuators in several respects :
SAR
MSAR
MUSAR
Regulating duty actuator
Sensor for actuator, i.e.
position transmitter at actuator
(potentiometer or inductive
LVDT)
Signal converter for SAR i.e.
Electronic position transducer
(RWG 1001/RWG 2002) or
inductive position transmitter
(IWG 1002/ IWG 1003).
CU01
V
M
MU
SE
W
XR
YR
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Electronic positioner
Regulating valve
Sensor for regulating valve
Signal converter for sensor
Setting nominal value
Reference input
Input value at controller
Output value at electronic
:
:
:
positioner
Torque for regulating duty should not exceed
Max. torque of actuator can be used for
For reversing service, duration of impulse
Electronic position transducer or precision
potentiometer should be used for remote
The motor should be short time duty
The SAR actuator basically consists of
control units as explained in following
Output speed of actuator max. 45 rpm.
1200 cycles / hour with motor power upto
0.55 kW & 600 cycles / hour with motor
Max. No. of starts-
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power above 0.55 kW.
50% of max. torque of actuator.
seating & unseating of the valve.
should be minimum of 50 ms.
position indication.
class S4 - 25%.
diagram.
- 4 pole motors are used to reduce overshoot
- Worm with high quality finish on flanks for
better efficiency
Disc springs on worm shaft are pre
compressed to reduce dead band when
While selecting Auma actuators for regulating
duty applications, following points should be
reversing.
-
noted :
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