In a full-service application, which three components have equal pressure?

In a full-service application, which three components have equal pressure?

• A. Brake pipe, auxiliary reservoir, main reservoir
• B. Brake pipe, auxiliary reservoir, brake cylinder
• C. Brake pipe, brake cylinder, main reservoir
• D. Auxiliary reservoir, brake cylinder, main reservoir

Answer: (B)

In a full-service application, the braking signal is a drop in brake pipe pressure. The triple valve detects this drop and allows air from the auxiliary reservoir to flow into the brake cylinder to apply the brakes. Air keeps moving until the brake cylinder pressure matches the brake pipe pressure. At that moment, the triple valve stops further flow from the auxiliary reservoir, and the brake pipe, auxiliary reservoir, and brake cylinder all sit at the same pressure. This equalization ensures a consistent, full braking effect and sets up the system to release when the signal pressure returns to normal.

In a full-service application, the braking signal is a drop in brake pipe pressure. The triple valve detects this drop and allows air from the auxiliary reservoir to flow into the brake cylinder to apply the brakes. Air keeps moving until the brake cylinder pressure matches the brake pipe pressure. At that moment, the triple valve stops further flow from the auxiliary reservoir, and the brake pipe, auxiliary reservoir, and brake cylinder all sit at the same pressure. This equalization ensures a consistent, full braking effect and sets up the system to release when the signal pressure returns to normal.