In brief
ZF's engine-driven compressor description distinguishes loaded operation from periods when additional air is unnecessary. Some designs can disengage the compressor through a clutch.
Useful to know
ZF's engine-driven compressor description distinguishes loaded operation from periods when additional air is unnecessary. Some designs can disengage the compressor through a clutch. [1]
Sufficient reservoir pressure therefore does not automatically mean zero compressor energy consumption. Compare control and mechanical connection rather than only maximum pressure.
Sources
For further detail and to check the information: