Practice question

What is the purpose of the anti-compounding (modulator) valve in a dual air brake system?

  1. It increases compressor speed
  2. It prevents the service brakes and spring brakes from being applied at the same time, which could damage components or cause severe lockup
  3. It cools the brake chambers
  4. It bleeds the wet tank automatically

Answer: B — It prevents the service brakes and spring brakes from being applied at the same time, which could damage components or cause severe lockup

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