Ancillary Equipment Control
For small tool power take-off, both flow and pressure must be regulated, given that the excavator will have more power available than required.
For wheeled excavators, brakes are supplied by back-up accumulators which must be charged at all times. The dual check valve makes sure that the lower pressure accumulator is always referenced to the supply. The unloading valve will re-charge the accumulators each time they drop below 85% of their required setting.
Pilot System Control
Most excavators now utilise pilot controls to their spool banks. The pilot supply will come from a separate system with all of the controls necessary to divert and limit the oil flow and pressure. There are many solutions to these requirements. both proportional and conventional. Integrated circuits provide an ideal carrier for these smaller. low pressure systems.