971B UniMag Cold Cathode

Vacuum Transducers
The 971B UniMag vacuum transducer offers a measurement range from 1×10-8Torr to 5×10-3 Torr and is based on cold cathode inverted magnetron sensor technology. The 971B is a cost effective solution for base pressure measurement and control. In addition to its small size, broad range and lower cost, the 971 UniMag Cold Cathode Inverted Magnetron Transducer Vacuum Gauge can be operated via digital communication or as an autonomous analog unit.

Key features

  • Absolute measurement range from 1×10-8 to 0.005 Torr
  • The cold cathode anode module design is user serviceable to decrease downtime
  • Ease of operation via analog output, RS232, or RS485
  • Optional integrated touch-screen display available for local pressure indication
  • Three user configurable relays for process control
  • Small footprint design provides a compact transducer solution

Digital Communications

Series 970B vacuum transducers feature RS232, RS485, and EtherCAT (972B only) digital communications interface for setup of transducer parameters and to provide real time pressure measurement. The digital interface can be used to control pressure units, baud rate, address, factory default, user tag, RS485 test, gas correction; set point functions: value, hysteresis, direction, HV enable, protect, control set point, and gas type.

0.5 VDC per Decade Analog Output

All Series 970B transducers have an analog pressure output of 0.5 VDC per decade that can be interfaced to external analog equipment for pressure readout or control. Other analog outputs and curves can be selected via the digital user interface. It can emulate analog voltage outputs from a variety of other vacuum transducers. The emulation feature can be used to upgrade and replace other vendors’ gauges in OEM applications without changing system software.

Optional Integrated Touch-screen Display

The optional integrated touch-screen display is user configurable; the user can change pressure units, orientation and has access to set point parameters as well as gas type. The display also indicates the status of the available set point relays. Displayed pressure reading from individual sensors or combined reading can be seen from >5 meters away on the high contrast display.

Process Control Relays

The Series 970B has up to three mechanical SPST relays which can be used for process control, examples are interlocking valves or pumps. Relay contacts are rated at 1 amp for 30 VAC or VDC, resistive loads.


The Series 970B Transducers are compact, low cost measurement solutions for vacuum users operating within the pressure range of atmosphere to 10-8 Torr. The small size of the Series 970B transducers makes them ideal for system integrators looking to reduce footprint and enable miniaturization.

Applications include:

  • Analytical equipment (mass spectrometer control)
  • Scanning electron microscopes
  • Coating systems
  • Semiconductor loadlock pressure control
  • General vacuum base pressure measurement