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Fail Safe Actuation
Fail Safe Operation – operating an actuator when power is lost
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When automatic valve control must be managed and controlled after the power is out. Where flow must be maintained or operated quickly and efficiently for safety.
Effective for:
- Isolation Valves to separate one system from another upon loss of power, such as heat exchangers in heating or cooling systems
- Ventilation damper systems to provide or prevent air flow in emergency situations where power is lost
- Steam or Fuel supply valves that need to be shut or opened with loss of power
- Remote valves where power is intermittently disrupted, but control is still needed
ProMation Engineering has two distinct lines of fail-safe solutions to protect lives and processes.
- Mechanical - Spring Return Actuators (PA Series)
- Electrical - Battery Back-up for All Actuators(PBU Series)
With the use of either fail-safe line that ProMation Engineering offers, users can rest at ease knowing their processes or facilities are fully protected in the event of power outage.
PA Series Spring Return Actuators
The PA Series quarter turn spring return actuators compress several internal springs in one direction and use the springs to drive in the opposite direction. While power is present, the actuator will respond to drive control signals depending on the method of control chosen.
For an on/off, or 2 position, the motor will drive until it reaches its spring-loaded position and spring in the opposite direction with loss of power. For Proportional control, the unit responds to an analog control signal for positioning, whether to open or close (clockwise or counterclockwise). In both control options, when power is lost, the springs drive the actuator, either clockwise or counterclockwise, to its unsprung position.
- Torques from 445"lbs / 50Nm to 2300"lbs / 260Nm.
- 120/230VAC (On/Off or Proportional Control) or 24VAC/DC (On/Off only) supply voltages.
- Integral Manual Handwheel option available. (Factory installed option).
- Mechanical connections utilize an ISO5211 mounting with an 8 point female drive.
PBU Series Battery Back-Up System for Electric Actuators
The ProMation battery back-up units (PBU) can provide power to operate any electric actuator upon loss of power. The PBU's are designed to provide power to all ProMation actuators for a minimum of 5 cycles at full torque load.
The PBU series utilizes proven battery systems and switching electronics that are compatible with all ProMation Engineering actuators. The separate local control station has field selectable fail-safe position, battery status and power indicators that can be used in conjunction with 2 position or proportionally controlled models.
- Automatic power control switching system to charge the battery and then provide power to actuator when needed
- Field Selectable Fail Direction
- Readily available sealed Battery packs
- Lockable Fiberglass NEMA 4X enclosure
- Simple User Interface with Indication Lights
- Cold Weather functionality available
ProMation Engineering, Inc., 16138 Flight Path Dr., Brooksville, FL 34604
Tel: 352-544-8436 • info@promationei.com
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