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Model Q45P/R pH/ORP Monitor from Analytical Technology

ATI's versatile Q45P/R pH/ORP system is designed for use in all industrial and municipal applications. The sensors are engineered to function normally in applications where conventional sensors quickly fail.

Conventional pH/ORP sensors have an "open reference system", which means the reference element and electrolyte are in contact with the process. This allows chemicals to diffuse into the reference chamber and alter the reference system. As the reference junction becomes contaminated, the reference potential shifts. As chemicals attack the silver reference wire, the reference potential shifts and the sensor no longer functions. When any of these problems occur, cleaning and calibration cycles increase and the sensors fail much faster, all of which costs you time and money.

The differential pH/ORP sensors utilize a "sealed reference system", where the sensors are constructed with a second glass pH electrode as the reference element. The glass reference system protects the sensor from chemical poisons (sulfide, cyanide, chlorine, bisulfates, etc.) that destroy conventional pH sensors.

A large volume, dual junction saltbridge is used to maximize the in service time of the sensor. The annular junction provides a large surface area to minimize the chance of fouling. Large electrolyte volume and dual junctions minimize contamination of the reference solution. The replaceable saltbridge allows for easy and inexpensive sensor regeneration.

As integral preamplifier is encapsulated in the body of the sensor. This creates a low impedance signal output which ensures stable readings in harsh environments and maximizes the distance between sensor and analyzer. Sensor diagnostics are used to alarm the user in the event of electrode breakage, loss of sensor seal integrity or integral temperature sensor failure.

Sensor electrodes can be user specified to ensure measurement reliability and maximum sensor lifetime. The type of glass used in the pH electrodes can be selected for optimal performance. The metal electrode used for ORP measurement can be platinum or gold, depending on the chemical makeup of the process solution.

All sensors are available in several mounting configurations. The 1" NPT convertible style sensor is constructed of PEEK, a high performance thermoplastic that provides outstanding mechanical strength and chemical resistance. An insertion style sensor is available in 316SS for hot tap applications. The mounting hardware for the insertion sensor is either CPVC of 316SS and is mounted using a 1 1/4" NPT full ported ball valve. The sensors are also available with 1 1/2" or 2" sanitary style fittings.

The Q45P/R Auto-Clean System is designed to extend sensor cleaning intervals on pH and ORP sensors that are mounted in applications containing high levels of solids contamination. The Auto-Clean System uses high pressure air to remove contaminants from the face of the sensor automatically.

The Auto-Clean system utilizes a self contained compressor and air cylinder to generate a series of high pressure air blasts. Each cleaning cycle lasts approximately 2 minutes, during which the monitor outputs are placed in a HOLD condition to prevent false readings or alarms.

The concentration of solids in the process will determine the cleaning frequency of the system. The user can vary the cleaning cycle frequency from as often as once very two hours to as little as once a day.

Although the Q45 Auto-Clean System can greatly extend sensor cleaning intervals, the user must still clean and calibrate the sensor at some interval. For a typical pH or ORP measurement in wastewater treatment, the system can extend weekly cleaning intervals to once every 3 months. Cleaning systems are not suitable for removing hard scale such as that caused by lime.

Standard Sensor Compatibility

The Q45P/R monitors can be easily configured to accept the input from a traditional combination sensor. For applications where a specialty sensor is required, ATI offers a line of standard sensors to meet your needs.

The unique "Lock-N-Load" system is pipe mounted and provides quick and easy isolation of the sensor from a flowing stream. The self sealing sensor holder allows the sensor to be removed for maintenance without shutting down the process stream.

For high purity water (conductivity below 20 microSiemens), a special sensor is used in conjunction with a stainless steel flow assembly. This system is designed to minimize interference (noise, streaming potentials, CO2, etc.) and provides a stable pH measurement.