English to Swedish Tech/Engineering Agriculture

Auxiliary spools förekommer i en handbok för en rundbalspress i avsnittet som beskriver traktorns hydraulsystem:

Note: Although it is possible to operate the XXX with a load-sensing system via.
the tractor auxiliary spools, i.e. continuous oil flow (control valve is set to open
centre set-up and flow is set to 50 lit./min. from the tractor), YYY do not
recommend operating the XXX in this set-up, as controlling the oil flow is too
variable from one tractor to another, and there is also a 20 kW pto power loss with
it’s associated over-heating of the oil.

Undrar om det kan översättas med Hjälpspolar?