E2H90 Series

On/Off Rotary Actuator

The E2H90 Electro-Hydraulic Rotary Actuator is designed & engineered for ON/OFF applications.

electro hydraulic actuator

Compact Self-Contained Electro-Hydraulic Rotary Actuator for On/Off Applications

Cowan E2H90 Series Self-Contained Electro-Hydraulic Rotary Valve Actuators are used for industrial process valves where highly reliable, controlled and Emergency Shut-down are required. They are used to automate rotary type valves such as: ball and butterfly valves.

For valve automation applications that require emergency shutoff valve automation, we recommend the E2H-ESD.


  • Torque up to 2,650,000 in-lbs
  • On/Off Service
  • Fail-Last, Fail-Close or Fail-Open
  • Spring-Return configuration available
  • Manual Override is Standard
  • Dual Hydraulic Filtering System: allows ease of maintenance

Independent and Adjustable Open/Close Time

The system flow rate is designed to be 20L/min. For example, the measure ESD time of a size 09 electro-hydraulic actuator is less than three seconds.

By independently setting an open/close adjustment valve in the hydraulic control system, the length of time to operate the valve by the actuator can be strictly controlled. 

For example it can close or open the valve in a natural gas pipeline quickly (less than 10s) to block it, or slowly close (more than 120s) the valve to avoid the water hammer effect in a production oil pipeline.



Isolation, on/off


Double or single acting

Fail system

Hydraulic Accumulators or Springs

Driven by

Accumulators, sized to 2 strokes


200-240 Vac/1 Phase/3 Phase
380-480 Vac/3 Phase
500-690 Vac/3 Phase & Custom

Control panel

Integral or remote

Ambient temperature

(-40 to +70 C)



Classification for hazardous areas

Explosion-proof rating: Ex d IIB/IIC T4


Digital (standard)
Feedback by HART,PROFIT NET,PROFIT BUS (options)


Local, remote and ESD function can be configured
Open and close indication
Program partial stroke test (PST)


Duty cycle S5 (15 min continue service)

Power consumption

Only when recharging accumulators

Movement Lock

Complete after each operation

Manual override

Manual hydraulic pump


Speed control for Open and Close


Horizontal or vertical (ISO, MSS, Custom)

Safety Integrity level

SIL 2 (HFT)=0 ; SIL 3 (HFT>=1)

Valve Compatibility

Our Series E2H90 Self-Contained Electro-hydraulic Rotary Actuator is compatible with any process valve that requires rotary motion.

knife gate valve actuator

Butterfly Valve

gate valve actuator

Plug Valve

Segmented Ball Valve

Trunion Ball Valve

Design and Materials

Roll-over the red circle hotspots for more details: 

electro hydraulic actuator



Integrated Hydraulic Control System




Power & Drive Modules

Quarter turn stroke: -5° to 95° adjustable
The cylinder features dual seals to guarantee zero leakage
Symmetric and canted yokes are available to satisfy various valve torque profiles


Explosion Proof Electronic Control Panel





Actuator mechanical Design

Scotch Yoke

Scotch Yoke

Failure system

Spring return, fully sealed in a compact canister. Welding's Certified to CSA 47.1 Division 2. Option for hydraulic return on preloads higher than 306,000 lbs.-in

Hydraulic accumulators system designed to 2 strokes. Option for spring is available 

Fail Function

Fail on Loss of power & ESD Signal

Fail on Loss of ESD Signal

Operational ambient temperature rating

(-50C TO 40C) 

(-40C TO 70C) 

Control Panel

Standard: Installed on the unit wired and tested
Option: Remote 

Standard: Installed on the unit wired and tested
Option: Remote 


Standard-Power/Overload/Open/Closed & PST light indicators. Open/Close/push buttons
Option: HMI-Multi Color Touch Screen (only available with the smart PCL option)

Standard LCD Screen, circuit printed board. Navigation buttons, Open/Close buttons. Local, Remote selector


Standard: Discrete. Open/close/ESD/PST
Option: Smart PCL, 4-20ma control, 4-20 ma c/w HART, PROFIBUS,PROFINET.

Standard: Discrete. Open/close/ESD/PST

Environmental Protection 



Hazardous Area classification and certifications

CSA or uL or cUL CI1,Div1&2,Gr C&D

Ex d IIC T6

Power Supply Voltage

120VAC/60Hz/Single phase. Options available

220VAC/50Hz/Single phase. Options available

Manual Override

Standard: Manual Hydraulic pump

Standard: Manual Hydraulic pump

Partial Stroke

Comes standard, set at a set position. Standard 20% open. Speed adjustable

Comes standard, set at a set position. Standard 20% open

Fail safe time 

Fast- Less than 15 secs for all models. Adjustable and padlock able

Standard : Fixed. Not adjustable.
Option: Adjustable, not lockable

Stroke operation

Directly driven by the hydraulic pump. No down time, recharge not needed

Driven by the pressurized fluid in the accumulators. Accumulators sized to 2 strokes, after this accumulators must recharge

Recharge time

Not required. Unit is always available to stroke the valve

Between 15 to 30 mins depending on the model

Modular Design

Yes, Controls and hydraulics can be provided remotely mounted as a standard design if required


Hydraulic Design

All Hydraulic components and sensors are integrated into a compact manifold block. The complete hydraulic system is Fully enclose and pad-lockable

All hydraulic valves are included in a enclosed cabinet, interconnection between components is all done with stainless steel  tubbing and fittings. 

Mechanical travel stops 

Mechanical travel stops +/- 5%  and local position indicator

Mechanical travel stops +/- 5%  and local position indicator

SIL Certification 

SIL 3 (Pending)

SIL 2 (HFT)=0 ; SIL 3 (HFT>=1) 

Lifting lugs