It might be the long way around,
but could use the pressure tank's switch contacts to operate a lower voltage relay coil. Relay contacts dealing with the 48VDC power.
A properly sized resistor or Zener would take care of the 48V to lower voltage relay coil.
Plus a Schottky flyback diode on the relay coil.
Pretty simple stuff. Don't get scared off by fancy unfamiliar words.
I see it as avoiding replacing burned switch contacts.
If the relay contacts burn, simple to replace the relay.
Choose the relay carefully, and probably want to have a spare on hand. Just in case.
Not saying it is a great idea, but it would work.
Anybody have thoughts about that?
G-