Righteous Trip

The first dual parallel-redundant, on-line repairable, on-line testable hydraulic trip system
TUV Certified SIL 3.

Bona Fide

The TetraSentry has genuine reliability which means you don’t have to worry whether it’s going to trip your turbine when you need it to and it won’t trip your turbine when you don’t.

Small and Simple

Most redundant hydraulic trip systems take up as much space as a small SUV, are about as complex and have nearly as many parts. The TetraSentry is simple, has very few parts and it’s about the size of your smallest Operator.

Pop Quiz

The Tetrasentry loves to be tested on-line; which is good because it’s really the only way for you to be sure that your hydraulic trip system is working.


The TetraSentry is a dual parallel-redundant hydraulic trip block that’s on-line testable and on-line repairable. The TetraSentry is connected to the hydraulic trip header in parallel with the turbine trip valve. During a trip action, the high capacity solenoid valves dump the trip header fluid to the reservoir faster than the supply orifice can refill it. Testing is accomplished using pressure transmitters to monitor the state of each solenoid valve. They provide feedback to the control system to allow confirmation of the success of each step in the test. Isolation valves allow each pair of solenoid valves to be taken out of service and replaced without compromising the system’s ability to trip.


Standard Features

  • Manifold-mounted components
    • Solenoid valves (4)
    • Full-flow block valves (4)
    • Restriction Orifices (4)
    • Cartridge filters
  • Pressure Transmitters (2)
  • Stainless steel junction box with terminal blocks
  • Support frame
  • Companion flanges
  • Viton O-rings and seals
  • Fully tubed and wired
  • TUV Certified SIL3

Optional Features

  • Buna-N O-rings and seals
  • Trip header pressure transmitters
  • Class 1, Div 1 electrical components Drain accumulators



Feature Description
Manifold Aluminum
Frame Galvanized Steel
Junction Box Stainless Steel

Performance and Power

Feature Description
System CV 10
Solenoid Voltage 24VDC, 120VDC, 120VAC
Solenoid Power 30W


Feature Description
Junction Box 12”x12”x6”
Manifold 10”x10”x20”
Package 20”x30”x63”


Feature Description
W/ Aluminum Manifold 520lb
W/ Stainless Steel Manifold 850lb
W/ Header Pressure Transmitters + 27lb