Mars 10/25 LP Open On Fall Pressure M43343

The Mars M43343 is a low pressure switch with settings of approximately 10 and 25 PSI, opening on a fall in pressure.

Open on fall is the defining action of a low pressure control: contacts closed in normal operation, opening when pressure drops to the cut-out.

The low settings here, 10 PSI cut-out with 25 PSI cut-in, suit low temperature refrigeration, where evaporating pressures are far below those in air conditioning. A freezer application operating at these pressures would be entirely normal, whereas an air conditioning system reaching 10 PSI suction would be severely undercharged or restricted.

This illustrates why low pressure controls cannot be selected generically. The setpoint must be below the system's normal minimum operating suction pressure, with enough margin that ordinary variation does not trip it, but high enough that it acts before the system runs in a genuinely damaging condition.

Establishing that requires knowing the application's design evaporating temperature and converting it to pressure for the refrigerant in use.

A control set too low provides little protection; one set too high causes nuisance trips during normal pull-down.

Applications include low temperature commercial refrigeration, freezers, and refrigeration systems.

Brand

Mars

SKU

M43343

Category

Pressure Switches

Weight

0.2 lbs

Dimensions

3.50" x 2.00" x 1.50"

Price

$52.00

Availability

In stock

Rating

0 / 5.0