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Electric actuator AT 3911 (200-800 Nm)

Electric actuator for On/Off, positioning or modulating of ball valves, butterfly valves or where a 90° rotation is needed.

Torque200 Nm to 800 Nm


Article number Performance Torque (Nm) Amount
AT 3911-20 Electric modulating, Electric on/off 200
AT 3911-25 Electric modulating, Electric on/off 250
AT 3911-60 Electric modulating, Electric on/off 600
AT 3911-80 Electric modulating, Electric on/off 800
AT 3911-20X Electric ATEX classified 200
AT 3911-25X Electric ATEX classified 250
AT 3911-60X Electric ATEX classified 600
AT 3911-80X Electric ATEX classified 800

Product information

Range of application

Weather-proof actuator for On/Off, positioning or modulating manuvering for ball- and butterfly valves. Torque from 200 to800 Nm.


UEC.11 Actuator for valve, electric, two-position without spring return
Actuator Bernard Electrical AT 3911 for 90° maneuvering of ball-, butterfly- as well as plug valves

Quality assurance

CE marked

EC directives 2004/108/EC, 2006/95/EC, following the standards in EN 61000-6-4, EN 61000-6-2, EN 60034-1 och EN 60529.

IP 67 rated

Material specification

DetailMaterial Surface treatment
1BodyAluminum Zinc primer, epoxy layer and RAL 5002 blue polyurethane top coat
2CoverAluminumZinc primer, epoxy layer and RAL 5002 blue polyurethane top coat
3Drive shaftMassive steelUntreated

Dimension and weight

Actuator/ Fig. noDrift shaft*ABCWeight
Dimension in mm, weight in kg. *Possible to get in requested sizes, parallel or in a 45° rotationDimension in mm, weight in kg. *Possible to get in requested sizes, parallel or in a 45° rotation

Dimension and weight

Actuator / Fig. noDrift shaft*ABCWeight
3911-20-2B3PDepending on valve47938933625
3911-25-8B3PDepending on valve45938933622
3911-60-8B3PDepending on valve52838933627
3911-80-8C3PDepending on valve52838933628
Dimension in mm, weight in kg. *Possible to get in requested sizes, parallel, keyway or in a 45° rotation.Dimension in mm, weight in kg. *Possible to get in requested sizes, parallel, keyway or in a 45° rotation.

Function and design

Standard version

Reversible actuator in four different sizes for 0-90° movement, adjustable through a combination of cams, mechanical end stop and/or torque switches.

The actuator is a compact combination of an electric motor with thermal protection and a self-locking worm gear. As standard with a hand wheel and position indicator.

The actuator mounting dimensions in relation to the fittings are according to ISO 5211.

Design lifetime 20 000 cycles for On/Off or 300 000 starts for positioning. Tested according to EN 15714-2 class A and B

Standard performance

Motor dutyS4-30% ED, 360 starter/h max. S4-50% for modulating class III S4-100% for continues modulating
Temperature -20°C to +60°C
Anti condensation heaterYes
Thermal overload protectionThermostats

Permanently lubricated gear

Cable entries2 st.M20x1,5
End switches250V, max 16A
Torque switchesYes
Terminal block8 connections

Technical data

Actuator 3911 On/Off

Torque NmOperating time (50 Hz) sISO-connectiom230 V AC 50 Hz Ampere400 V AC 50 Hz Ampere24 VDC
252502505, 10, 30, 50F07/100,90,60,030,50,30,03
6060060030, 60F07/101,71,20,060,80,30,03-
8080080030, 60F12320,9

Accessories and options

Standard version, see above.

Possible options and variants

Actuator Intelli+, see seperate datasheets for possible features, such as summer alarm, bus-control, walking-time control etc.

Power supply 3-phase

380/415 V - 50Hz, 440/460 V - 60 Hz

230 V - 50 Hz, 220/230 V - 60 Hz

500 V - 50 Hz eller 5775 V - 60 Hz

Phase 1

110, 115, 120, 220 V - 50 Hz

115 V-60 Hz

24V - 50 Hz


24, 48, 110 or 220 VDC

For other time periods, contact Armatec

For an off-shore painted actuator, contact Armatec

For an ATEX-rated actuator, contact Armatec


During all work with the actuator the power MUST be disconnected.
- The actuator must be connected as per the wiring diagram, see the manual.
- Each actuator must be powered by an individual switch or relay contact, minimum 16A,to prevent cross-feed between the actuators.
- At outdoor installation, the actuator should be protected by a roof or cap.
- Installation with the motor downwards should be avoided.
- Turn the valve with the control unit's hand wheel to centre position. See indication on top of the device.
- Always connect the heater.
- Check that the actuator turns the valve in the desired direction.
- The correct limit switch (open or closed) shall break the motor current.
- Cable entries must comply at least to the lowest protection class of devices.

See the manual for start-up, storage and maintenance


Article number, manufacturer, serial number, voltage and current.
Wiring diagram is placed by the motor at delivery.

Options for control

Control signal230 V, 50 Hz3-phase 400 V, 50 Hz24 V
4-20 mA or 0-10 VMinigam, Integral,PosigamIntelli, Integral, PosigamIntelli, Integral, Posigam
Profibus DPIntelli, Integral, PosigamIntelli, Integral, PosigamIntelli, Integral, Posigam

How to order

Example: 3911-25-8B3A
Fig. n0.SizeOperating timeConnectionVoltageOptions
Example: 3911-25-8B3P (Regulation with an Intelli ecu)
* 4, 6, 10 or 15 depending on needed torque
** =Time: 1=3s, 2=5s, 3=6s, 4=10 s, 5=15s, 6=20s, 7=25s, 8=30s, 9=35s, 10=45s, 11=50s, 12=60s
*** A=F05/07, B=F07/10, C=F12
**** 0=24 VDC, 3=230 VAC, 4=400 VAC
***** A=On/Off, B=Integral, C=Posigam, D=Minigam, E=1000 Ohm POT, P=Intelli