As with electrics, a distinction is made in fluid technology between series and parallel resistances.
- For series circuits - as is the case for pipelines - the individual resistances are added (series circuit). This means, for example for the "pressure-free" circulation of the pump through a directional valve and a filter including pipes, that a Δp of 8 to 10 bar is easily created.
- Parallel resistances result in a flow division, wherein the flow in the individual branches is inversely proportional to the resistance to be overcome (parallel circuit). This means, for example that a synchronisation of multiple cylinders is practically impossible without auxiliary equipment.