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HaloSense Residual Chlorine Analyzer

The HaloSense range of Residual Chlorine Meters are used in many applications requiring the measurement of total or free residual chlorine for chlorine analyzers or residual chlorine dosing control.

A range of residual chlorine meters using the HaloSense sensors means that you can get exactly what you need and nothing that you don't. From a low cost no-frills chlorine controller (CRONOS) to a colour touch screen, Remote Access & Control controller (CRIUS) - and all with the same great sensors!

"The Residual Chlorine Analyzers from Pi are the best we've ever used" Dr Lester Simmonds, UK

Residual Chlorine Analyzer Key Benefits

• Low cost of ownership
• Reduced pH dependency
• Stable and reliable Residual Chlorine Monitor
• Free chlorine analyzer
• Total chlorine analyzers
• Combined chlorine analyzers
• Bufferless chlorine meter
• Reagentless chlorine meter
• Residual Chlorine Analyzer
• Download the Brochure Now - No registrations or log-ons!

New! Residual Chlorine Meters now available with up to 12 chlorine sensor inputs, reducing the cost per point of your bufferless residual chlorine analyzers. Chlorination control is now simpler and cheaper than ever!

Residual Chlorine Analyzer Applications

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"I've bought more than 100 chlorine analyzers from Pi and I think they're great!" John Clark, USA

• Continuous chlorine monitoring
• Water treatment plant residual chlorine control
• Secondary chlorination free chlorine control
• Distribution monitoring for total residual chlorine
• Cooling tower chlorine monitoring and control
• Pasteuriser chlorine dosing control
• Seawater chlorination control
• Chlorine in seawater

Anywhere you have a requirement to measure residual free or total chlorine is a suitable application for the HaloSense. The HaloSense chlorine meter range is particularly suited to working in sites where reliability and ease of use are most important.

Principle of Operation

The membraned amperometric chlorine sensor is enhanced with a third, reference, electrode which eliminates zero drift. pH correction is often not required at all. (NB. These chlorine sensors are often known as polarographic chlorine sensors although this is a misuse of the word polarographic). Its unique design means that pH correction is not usually required at all, completely eliminating reagents.

In addition to the state of the art potentiostatic chronoamperometric free chlorine and total chlorine sensors, the HaloSense range of residual chlorine analyzers has all the functionality that you need, and more. Simply choose the CRONOS, CRIUS^® or CRATOS controller to give you the highest quality chlorine meter, with all the functionality you need at the lowest price possible. This means that you pay for everything that you need and nothing you don't, without sacrificing the quality of measurement!

The chlorine sensor used by the Total Free Chlorine Meter and the Residual Free Chlorine Meter are both largely pH independent meaning that both chlorine sensors are bufferless and reagentless. They are both amperometric chlorine sensors and both show remarkable sensitivity and stability. For those making a chlorine measurement at high pH ( > pH 8.5) on variable pH water it is possible to provide pH compensation from either a pH sensor connected to the chlorine analyzer or from an external pH meter.

The chlorine sensors work by seperating the electrodes that perform the chlorine measurement from the sample, by a membrane. This membrane allows the free residual chlorine (HOCl and OCl^-) or the Total Residual Chlorine (HOCl and OCl^- plus chloramines) through the membrane. Inside the sensor the residual chlorine meets the electrolyte which is at a low pH. This converts the majority of the OCl^- to HOCl. The HOCl is reduced at the gold working electrode and the current generated is proportional to the Free Chlorine or Total Chlorine present, and the chlorine analyzer gives a reading in chlorine ppm or mg/l.

This technique is the most advanced method of continous chlorine measurement and has many benefits to the user including a very stable chlorine measurement and better chlorine dosing control.

In addition to total free chlorine meters, the free chlorine analyzer measures the chlorine concentration and the chlorine analyzer can then control the chlorine dosing using a variety of control algorithms including PID control.

The Residual Cl₂ Analyzer is bufferless and reagent free, meaning it has a low total cost of ownership and with maintenance intervals at 3 or even 6 months, the bufferless Chlorine Meter is fast becoming the instrument of choice for the engineer who wants the best chlorine meter at the best price.

The CRONOS, CRIUS and CRATOS Free and Total Residual Chlorine Analyzers are equipped with process control options, datalogging, relay outputs, serial comms, (TCP, Ethernet, ModBus are available now with Profibus available soon). Remote Access of the chlorine analyzer (including remote access to all control options) is available via the internet, and via a LAN. In fact the CRIUS^® HaloSense chlorine analyzers have all the options you could want in a Chlorine Analyzer or controller whilst the CRONOS maintains a low cost and is particularly great value for money!

Autoflush and AutoCal

As described in seperate brochures, the HaloSense can come equipped to automatically clean itself or calibrate at user defined intervals with all the benefits of no operator intervention for 6 months. The Autoflush is particularly useful in food preparation, pulp and paper, and many applications where there is likely to be a build up of solids in the sample. The AutoCal is used to give completely operator free operation for up to 6 months.

pH Compensation

For some applications with high and variable pH, pH compensation can improve the accuracy of the chlorine readings. For pH compensation to be valid it must be done with the highest quality pH sensors and with chlorine sensors that have a reduced susceptibility to varying pH, such as those used in the HaloSense range of chlorine analyzers.