Beck 901 Pressure Switches

A pressure switch gives an on/off contact at one set point. A pressure transmitter gives a continuous 4 to 20 mA or 0 to 10 V signal proportional to pressure, so a PLC can display, trend and control it. Use a switch for protection and alarms, and a transmitter when you need the actual value.

It's the difference between the pressure at which the switch trips and the pressure at which it resets. A small differential gives a precise alarm. A larger one stops a pump or compressor starting and stopping too often. On the adjustable Beck 901 it depends on the model, from 3 mbar on the 5 to 20 mbar range to 0.5 to 2 bar on the 12 bar models.

Choose Prescal® if the set point may change or you want to set it on site. The scaled knob sets it without a pressure gauge. Choose factory-set if the set point is fixed, for example on OEM machines or safety trips. Beck sets it to your value within ±10%, so every switch in a batch behaves the same.

Yes, when the materials match the medium. Choose the diaphragm (NBR, silicone, FKM or EPDM) and the connection (PA, PPS, PVDF, brass or stainless steel) for your liquid or gas. Media can reach 85 °C as standard, or 130 °C with a metal or PPS connection. Tell us the medium and we'll confirm the combination.

Yes. The adjustable 901 vacuum models switch between -5 and -700 mbar, and factory-set models go down to -900 mbar. The 901.8x differential models switch between 5 and 50 mbar, for example across a filter or a fan. For HVAC air and water systems, see our HVAC differential pressure switches.

For hazardous areas, choose the ATEX 901 Ex, adjustable or factory-set, for Ex zones 1, 2, 21 and 22, which cover both gas and dust atmospheres. For machines built for North American markets, choose the UL-approved 901, which conforms to ANSI/UL 508 and CSA C22.2 No. 14.