Thumbnail Filmstrip of PP-7 Push/Pull Trailer Supply Valve - Replaces Bendix 288241X Images
- PP-7 Push/Pull Trailer Supply Valve
- Automatic pressure release: 40 psi
- Threaded exhaust port: 1/4" pipe thread
- Shaft Size: 5/16"
- Cross References: 288241, 287282, 287282X, R955288241, RKN20025, EBN288241N, OR288241X, WA106113, LPP3502, AV288241, PL-288241, SB285, 401137, 034079, 1093109, GN288241
The PP-7 push-pull control valve is a pressure sensitive, on/off control valve which will automatically return to the exhaust (button out) position when supply pressure is below the required minimum. It may be manually operated to either position when pressure is above the required minimum. Button configuration and lettering may vary depending on application. The automatic exhaust pressure is 40 psi.
The PP-7 is used to control the tractor protection system and is generally identified as the trailer air supply valve. The valve employs an air operated interlock in the lower body which will apply the trailer brakes when the tractor spring brakes are applied. The interlock insures that the tractor spring brake can not be applied without the trailer spring brakes also being applied. Normally this action will not affect the position of the PP-7 valve button. The interlock of tractor and trailer parking is a requirement of FMVSS 121.