
The QR-DO-108 dissolved oxygen controller is paired with a fluorescence dissolved oxygen controller
The outdoor waterproof and dustproof design is suitable for wall installation, coil installation and round pipe installation
Provide contact points for the automatic electrode cleaning device and program setting output
It is equipped with a backlight sensor and has both automatic and manual backlight setting functions
With automatic correction; Manual and automatic temperature compensation functions
The password lock and combination key enter the setting and calibration mode design to enhance security protection
It features the RS-485 standard MODBUS communication protocol and can be directly connected to digital systems



Ac power supply: 100V to 240VAC±10%, 50/60Hz
Dc power supply: 20 to 40VDC
Operating temperature: 0-50℃
Instrument dimensions: 144mm×144mm×115mm (H×W×D)
The protection grade complies with IP65 (NEMA 4)
Installation methods: wall mounting, panel mounting, and round pipe mounting
Hollowed-out dimensions: 138mm×138mm (H×W)
Weight: 0.8Kg

The fluorescence dissolved oxygen meter is based on the principle of fluorescence quenching. When blue light shines on fluorescent substances, it excites them and emits red light. Because oxygen molecules can carry away energy (quenching effect), the duration and intensity of the excited red light are inversely proportional to the concentration of oxygen molecules. By measuring the phase difference between the excited red light and the reference light and comparing it with the internal calibration value, the concentration of oxygen molecules can be calculated.

Ordering Guide
QR-DO-108
QR-DO-108-D (20-40VDC)
QR-DO-108-RS (RS-485 output)
QR-DO-108-DRS (20~40VDC) RS-485 output
Electrodes and accessories
MD1900 Optical dissolved oxygen sensor
Bracket