41B, 42B, 51B, 52B

PRESSURE SwITChES

The 41B, 42B, 51B and 52B Vacuum, Atmospheric, and Pressure Switches offer accurate

and reliable protection for vacuum equipment, atmospheric switching, and vacuum/pressure

processes. Designed for applications where a DC signal output is not required, these

switches provide relay outputs that are readily interfaced with alarms, valve actuators,

computers, process controllers, load locks and other protection devices.

The 41B and 42B models are referenced to atmospheric pressure, while the 51B and

52B products are referenced to vacuum. The 41B/42B switches are often used to ensure

a loadlock pressure has equilibrated to local atmospheric pressure before opening the

door. The trip point on MKS’ atmospheric switches can be set to trip above, below (reverse

calibration), or exactly at current atmospheric pressure. Applications for the 51B/52B

switches include soft pumping, gas box switching, and safety interlocks.

Features & Benefits

• Precisecontrolforawidevarietyof

production applications including

semiconductor processing tools, high

vacuum pumps, compressors, blowers,

medical equipment and machine tools

• Provideshighreliabilitywhichreduces

downtime and lowers the cost of

ownership

• Superbsetpointaccuracyandrepeat-

ability: 0.5% of F.S. increases process

control

• Corrosion-resistant:all-metal,all-welded

construction exposes only 316L S.S. and

• Switchrelaycanbesettoenergize

above or below set point for fail-safe

operation

• Lowhysteresisduetocapacitance

technology improves set point accuracy

over mechanical switches

• Factory-settrippointfrom5%to100%of

Full Scale means no need for personnel

to adjust the set point and elimination

of safety concerns from an erroneously

adjusted set point

• Fastresponseswitching:20msec

• Excellentlongtermstability

• Ruggedhighoverpressurerating

(2 × F.S. or 45 psia, whichever is greater)

for pressure cycling applications