The HSU-DA sequence valve connects primary and secondary system branches after the pressure requirements on a third branch have been satisfied. This valve can be circuited to be operated by multiple pressure settings.

As the pressure at port 1 overcomes the spring resistance, it moves the main sloop to connect ports 2 and 3. Because the spring chamber is connected (separately) to drain, back pressure at the operating ports will not affect the pressure setting.

Direct acting for fast, accurate response. Several pressure ranges are available. The cartridge is constructed of steel parts, and operating parts are hardened and ground as required. The cartridge is designed for easy service and field repair.