User Manual

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Siemens Actuators for fire and smoke protection dampers GRA126.1E/.., GRA326.1E/.. A6V10888424en
Building Technologies 2016-12-05
Technical design
The brushless DC motor ensures accurate speed control, torque monitoring for
protecting the actuator and the air damper, and provides a reliable failsafe function.
Mechanical spring ensure the failsafe function.
Mechanical design
Robust, lightweight all metal housing made from die-cast aluminium which guarantees
a long service life even under extreme environmental conditions.
Maintenance- and noise-free gear train with stall and overload protection for the life of
the actuator.
The spring has a factory-set preload of 5° to ensure tight shutoff for the fire and smoke
protection dampers.
A hole with a screw in the center of the actuator allows manual setting of the gears. A
hex wrench is supplied.
A perforated bracket with pin available, depending on the way the actuator is fixed.
All actuators come with prewired 0.9 m long connecting cables.
The actuators can be mounted on either side depending on the required direction of
rotation. All setting and operating elements are available on both sides of the actuator.
Fixed switching points at 5° and 80°.
Use
The temperature monitoring unit is ready connected to the actuator and is used for
forced control of motorized fire and smoke protection dampers should excessive
temperatures occur.
Mode of operation
The temperature monitoring unit contains 3 thermal fuses, two for monitoring the duct
temperature and 1 for the ambient temperature. If the temperature at any of these fuses
exceeds the level of 72 °C (Optional: 95 °C), the power supply will be irreversibly cut.
As a result, the return spring will drive the actuator to the failsafe position. A test button
is integrated for making functional checks. When pressed, the current path will be cut.
LED functions
š Red = Operating voltage OK.
Thermo sensor defect
š Green = Operating voltage OK
Thermo sensor OK
˜ Dark = No operating voltage
Drive motor
Spring return mechanism
in the event of power
failure
Basic components
Housing
Gear train
Spring preload
Manual adjustment
Mounting bracket
Electrical connection
Note
Auxiliary switches
Temperature
monitoring unit