BL-121-20 Pool and Spa Controller

Hanna InstrumentsSKU: BL-121-20

Sale price£1,291.76
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BL-121-20 includes all the advantages of the BL-121-10 as well as an optional flow cell for ease of maintenance. The bypass flow cell allows for calibration and maintenance of the probe without the need to shut down the recirculation pump. Ideal for swimming pools, hot tubs and spas.

BL-121 Pool and Spa Controller

The BL-121 Swimming Pool Controller is a complete system designed for maintaining swimming pool, hot tub, and spa disinfection water quality.

The controller is available in two versions:

  • Optional bypass flow cell included (BL-121-20) - ease of maintenance enhanced by allowing calibration and maintenance of the probe without the need to shut down the recirculation pump

  • Inline system (BL-121-10) allows for direct installation of probe and chemical injection fitting into existing piping.

Key features:

  • Multi-coloured LED indicators for dosing

  • Meter status and service

  • USB Connectivity

  • Real-time graph display

  • Automatic logging

  • Programmable alarms

  • Password protection

More information:

BL-121 uses a multiparameter digital HI-1036-1802 probe that incorporates pH, ORP and temperature sensors along with a matching pin. All readings are measured within the probe and the data transferred to the controller by a digital connection.

A digital connection and matching pin provide for stable, reliable measurement. Without these two components, electrical noise from recirculation pumps and ground loops can interfere, causing erratic readings and premature probe failure.

BL-121 has two built-in peristaltic chemical feed pumps that are proportionally controlled with adjustable flow rates. One of the pumps is used to dose acid while the other is used to dose chlorine. The effectiveness of the available Chlorine, as determined by ORP, is inversely related to the pH value of the water. A pool with a fixed concentration of chlorine will show a decrease in ORP as the pH of the water increases.

BL-121 also features a dosing consent feature that will not dose chlorine until the pH value is first corrected. It is possible to have a low ORP value even though there is sufficient chlorine. The dosing feature avoids this situation as well as preventing chemical wastage and having a higher chlorine concentration level than desired.

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