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Process monitoring device

PUC 28 / PUC 28 K


Process panel (Aluminium, anodised) for displaying air-conditioning data


Process monitoring system with plastic surface and inputs for humidity, temperature or external pressure transmitters

Special features

  • High level of accuracy and long-term stability through automatic zero-point calibration
  • Easy configuration of the measuring range, analog output, time constants and units via keyboard or RS 232 (optional)
  • PROFIBUS DP interface (optional)
  • Graphic LCD display
  • 2 floating switching relays
  • Selectable output signal 0 .. 10 V or 0/4 .. 20 mA
  • Selectable attenuation of the output signal from 0 .. 40 s
  • Acoustic alarm when the threshold value is out of range, acknowledgement via key
  • Calibration via calibration inputs led out of the front plate (optional)
  • PUC 28 K model: 2 pressure ports at the front panel for readjustment of the pos./neg. final value
  • Highly stable measurements thanks to cyclical self-calibration of the zero point
  • High level of overpressure protection even in the smallest measuring ranges protects the instrument against pressure peaks or incorrect operation
  • Scaleable measurement range offers increased measurement accuracy

The PUC 28 process monitoring system is especially suitable for pressure monitoring applications in cleanrooms, laboratories, pharmaceutical plants and operating theatres. The system has two electrical inputs for humidity, temperature or external pressure transmitters. The measurement values provided by these devices are displayed on the graphic LCD display. As well as recording differential pressure, it also measures positive and negative overpressure and is freely scalable within the measuring range.
Two optional contact points allow the user to connect visual or audible alarms that are triggered any time values rise above or fall below specified limits. These threshold values can be set as parameters both for the internal differential pressure sensor and for the external humidity, temperature or pressure transmitter. The transmitter can be configured easily via an RS 232 interface (optional) with software. This can also be performed using a keyboard and display. A selectable time constant allows the transmitter to be adjusted perfectly to the pressure conditions and thus ensures a stable output signal.
The PUC 28 is suitable for wall mounting in cleanrooms due to its smooth, solvent-resistant plastic surface. The device is easily integrated into central building control systems via the optional PROFIBUS DP interface. In this case, the Profibus connection acts as a gateway for the analogue signals from the external transmitters, which thus require no PROFIBUS DP interface of their own.

Measurement ranges
± 100 Pa or ± 250 Pa
freely scaleable within this range

Margin of error

± 0.5 % of max. value
(0.3 Pa margin of error for the reference)

0 .. 10 V (Ri > 2 kΩ)
0/4 .. 20 mA (Ri < 500 Ω) adjustable
2 contact points, 6 A, 230 VAC, may be configured as desired within this pressure range

Supply voltage
24 VDC, ± 10 % smoothed

Data interface (optional)

The instrument is available with an ISO factory calibration or DAkkS-accredited calibration certificate (optional).