Clean room pressure monitoring needs stable low-range measurements and fast alarms when conditions drift. HD50CR measures relative or differential low pressure across ±125 Pa using a silicon piezoresistive sensor with temperature compensation and an auto-zeroing function that supports stable readings over time without regular recalibration.
Built for documentation and integration, the unit combines transmitter and data logger functions in a wall flush-mount design with a brushed stainless steel front panel. Three analog outputs are available as 0/4...20 mA or 0...5/10 V, galvanically isolated, plus RS485 with Modbus-RTU 'Slave' protocol for sensor networks and Ethernet (RJ45) for local network access. A red electroluminescent display with inattinic red protection and a front keyboard support local operation and configuration.
Network features extend monitoring beyond the panel. The integrated web server allows configuration and real-time viewing from any browser on the same Ethernet network. If Internet access is available, data can be sent via e-mail, FTP or to a Cloud endpoint. Two alarm thresholds per quantity can be set with hysteresis and delay, with local buzzer, alarm LEDs (for the three quantities linked to analog outputs) and alarm e-mails.
Piezoresistive sensor measures ±125 Pa with 0.01 Pa resolution and typical ±0.35% accuracy of measuring span.
Automatic zero calibration runs at regular intervals by temporarily disconnecting pressure inputs via an internal solenoid valve.
Three channels provide either active 0/4...20 mA (max 500 Ω load) or 0\...5/10 V (min 10 kΩ load), galvanically isolated.
RS485 provides Modbus-RTU slave connection. Ethernet supports proprietary protocol and Modbus TCP/IP, with up to 10 TCP/IP clients.
Supports an optional combined relative humidity and temperature probe and calculates absolute humidity, dew point and wet bulb temperature.
Flush-mount design with IP65 protection on the front panel (with protective cap on USB connector) and 24 Vac/Vdc power supply.
