What is MOS and POS?

MOS is an acronym for M aintenance O verride S witch that it is used to override a switch (e.g. level switch, temperature switch,…) for maintenance like flushing or replacement.

POS is an acronym for P rocess O verride S witch; this switch can be used during start up of a machine to override a pressure switch, for example, that will prevent a compressor from starting.