Part Number: 800481
Crack pressure: 4 psi
Horizontal delivery ports: 1/2" pipe thread
Vertical delivery ports: 3/8" pipe thread
Does NOT include mounting bracket
This valve has two long bolts opposite the delivery ports
Relay valves are primarily used on vehicles to apply and release rear axle(s) service or parking brakes. When the driver applies the brakes, air travels through the delivery (in this case signal) line to the relay valve and moves an internal piston down. This closes the exhaust and opens the delivery of air to the brakes. The primary benefits of using a relay valve is that the high capacity of air needed for braking is delivered directly and does not have to travel up to the brake valve and then all the way to the brakes. The brake force is adjustable and when released the relay valve exhausts to atmosphere. Relay valves are generally mounted close to the chambers they serve and are available in both remote and reservoir mount designs.