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A smart, maintenance free system

PowerHalt’s PH3 offers one of the safest control options on the market – providing a hands-free operation with an electronic reset function as well as various control options.

PH3 Highlights

  • Universal applications
  • 1.5" to 4" sizes available with multiple activation options
  • Additional motor torque available on 3.5" to 4" sizes
  • Compact and lightweight
  • Maintenance free, smart system
  • Rigorous vibration, corrosion and endurance testing
  • Designed to withstand large temperature ranges
  • Low power consumption
  • Electronic reset for in-cab control/comfort when testing shut-off valve - No more lifting the hood to manually reset
  • A complete installation all in one box
  • CSA B621-14 and B622-14 compliance available
  • PH3 MKI Data Sheet
  • PH3 MKII Data Sheet

PH3 Specifics

  1. Weather Proof Connector
  2. Valve Position Feedback
  3. Electronic or Manual Valve Reset
  4. Corrosion Resistant Materials
  5. Maintenance Free Butterfly Valve Design
  6. 12 VDC or 24 VDC Systems
  7. 1.75-4” Valve Sizes Available

PH3 Control Options & Components

  1. POWERGUARD CONTROLLER (AUTOMATIC) This system provides hands-free activation of the shut-off valve. It has additional safety benefits by utilizing our PowerGuard Automatic controller and magnetic pick-up. This system includes a manual override for direct operation of the shut-off valve, which allows the operator to perform routine safety checks and tests
  2. OPERATOR CONTROL (MANUAL) Manually controlled shut-off valves are more economical than automatic systems. However, they should only be used when the operator works in close proximity to the engine and has a clear, safe, and accessible location for shutdown activation during an emergency
  3. MEMBRANE SWITCH Low profile membrane switch with trip, test and reset functions & LED lights
  4. TOGGLE SWITCH Military style switch with safety cover to prevent false trip hazards. Provides a manual means to shutdown the engine or test the valve
  5. PANEL INDICATOR LIGHT Get instant notofication on the status of your PowerHalt valve with this LED panel indicator warning light for your dash
  6. MAGNETIC PICK-UP Measures flywheel RPM and sends a signal to shut down the engine when engine runaway occurs

PH3 Systems Can Include:

All necessary hose adapters, clamps, and hardware required for an install. Weather tight plug & play wiring harness, custom to each application. Easy to install kits for many applications. Control option available with PowerGuard automatic overspeed limiter or manual PowerGuard

Technical Support

Installation: PowerHalt PH3 MKII Shut-off Valve

Congratulations on the purchase of your PowerHalt PH3 MKII Air Intake Emergency Shut-Off Valve by Pacbrake. Aran will be guiding you through the installation of your new system for on highway vehicles and stationary equipment with single and secondary trip speed applications.

Installation: PowerHalt PH3 Shut-Off Valve

Congratulations on the purchase of your PowerHalt PH3 Air Intake Emergency Shut-Off Valve by Pacbrake. Paul will be guiding you through the installation of your new system. From component overview to installation.

Programming & Testing Your PH3 Shut-Off Valve

Paul will walk you through programming and testing the trip speed of your PH3 PowerHalt Air Intake Emergency Shutoff Valve by Pacbrake, as well as some of the other options available to you.


Jason will be guiding you through troubleshooting the magnetic speed sensor included with your PowerHalt Air Intake Emergency Shut-Off Valve by Pacbrake.

Reading a PH3 Error Code

Paul will walk you through how to read an error code for PH3 PowerHalt Air Intake Emergency Shutoff Valves by Pacbrake.

FAQs and Troubleshooting

How do I know if my valve is closed?

The electronic reset PowerHalt Shut-Off Valve (PH3) has an indicator light on the membrane switch panel. When the valve is closed the red light will illuminate until the valve is re-opened.

How much power does my PowerHalt system require?

Electronic activation PowerHalt systems can be powered by 12 or 24 VDC. Manual activation kits are specific to either 12 or 24 VDC whereas the automatic activation kits are universal to either power source.

Once connected to power, manual activation kits will draw near 0mA of current while automatic activation kits will draw 30-35mA at idle.

Can I use my PH3 PowerHalt system to protect my auxiliary PTO/work-mode equipment?

Yes, if you have a PH3 system you are able to program a secondary set-point to protect your auxiliary PTO equipment. Refer to your PH3 Installation Manual for more details on how to activate and program your secondary set-point.

How do I choose my PowerHalt air shut-off valve trip speed?

If you have control over the engine speed: choose to set your trip speed at 30% above the engine rated RPM. Refer to your programming manual for set-up procedure.

If your engine runs at a constant speed: you can choose to set your trip speed at 10, 20, or 30% above the constant engine speed. Refer to your programming manual for set-up procedure.

Can the valve incorporate multiple auxiliary inputs from an external source?

The PowerHalt PH3 air shut-off valve series can incorporate multiple auxiliary inputs from external sources for activation of the shut-off valve in the event of emergency. Ideal for secondary emergency monitoring systems as well as multiple locations for manual override input.

What can I do about an offset flywheel?

In some cases, the factory sensor port on the bellhousing does not line up directly over the flywheel teeth. The sensor port may give a partial view of the flywheel which is offset by a gap or a machined edge. It is possible that a threaded speed sensor will not be able to sense speed from an offset flywheel.

Pacbrake recommends first installing the sensor into the port and checking if the system is able to read speed. You can check that the sensor is detecting speed by proceeding to Set and Test a Trip Speed. If setting and testing occur successfully, the sensor is able to read speed.

If the sensor cannot read speed, contact Pacbrake Support for an offset adapter (P/N: C50136) and a 3/8”-20 gear tooth speed sensor. The offset adapter is a sleeve with a 3/4”-16 external thread and a 3/8”-20 hole drilled off-center to allow the smaller sensor to be positioned directly over the offset flywheel teeth.

A more immediate solution would be to drill and tap a new sensor port in the correct position on the bell housing.

Warranty Registration

Register your product for warranty HERE.