Volvo EC460B - Main Relief Valve Operation (New)

Main relief valve operation(New)
The function of main relief valve is limit the maximum system pressure.
pc-OFF
1. Pump pressure is lower than the set-pressure.(close)
2. Pump pressure is reached to the set-pressure.(pilot poppet open) Main poppet open and pump line has
tank-connection.
pc-ON
1. Boost signal comes from port pc and push the piston to increase the tension of spring.
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