Mooddeell Q45D--OODOO Optical Dissolved Oxygen Monitor Green glow is simulated Optical Sensor Reduces Maintenance Costs

ATl’s Series Q45D has been providing reliable D.O. control in plants throughout the world for many years. Using a galvanic membraned sensor, this system is a proven performer in the most demanding applications. Dissolved Oxygen monitoring is critical for aeration system process control. Optimization of the biological process, whether it be carbonaceous removal, nitrification, or nitrification/denitrification, depends on maintaining proper D.O. levels. In addition, controlling blowers and aerators to operate at optimal level eliminates excess aeration and will result in large power savings for...

Optical D.O. sensors developed in the last few years use a technique that essentially measures the rate at which oxygen absorbs an optical signal generated within a membrane impregnated with a fluorescent dye. The dye within the optical element is excited by a pulse of light from an internal LED. This causes the dye to flouresce, or emit light of a different wavelength. The rate at which this emitted light decays (or is “quenched”) is proportional to molecular oxygen in the element. The higher the oxygen level, the faster the decay rate. Optical sensors do not have internal electrolyte, so maintenance...

Measurement Type: Dissolved Oxygen Sensor Type: Optical fluorescence quenching Range: 0-40.00 mg/l (or PPM) 0-200% Saturation Response Time: 90% in 150 seconds Accuracy: ± 0.05 PPM below 2 PPM Repeatability: ± 0.2 PPM from 2-10 PPM, ± 0.4 PPM above 10 PPM Electronic Linearity: ± 0.5% Zero Drift: < 1% full scale per month, non-cumulative Display: Backlit LCD, 0.5” Main Display Controls: 4 membrane switches on front of monitor Outputs: Two Isolated 4-20 mA, 575 ohms maximum Alarm Relay: Two SPDT, 5 A @ 230 VAC resistive Relay Coil: Programmable either normally energized or normally de-energized...