Residual Chlorine Analyser CRIUS^® 3500

The CRIUS^® 3500 Residual Chlorine Monitor is used in many applications requiring the measurement of chlorine concentration for chlorine monitoring or residual chlorine dosing control.

The chlorine sensor used by the Total Free Chlorine Monitors and the Residual Free Chlorine Monitors 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 analyser 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 analyser 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 measurement the free chlorine sensor determines the chlorine concentration and the chlorine analyser can control the chlorine dosing using a variety of control algorithms including PID control.

The Residual Cl₂ Analyser 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 Monitor is fast becoming the instrument of choice for the engineer who wants the best chlorine monitor at the best price.

The CRIUS^® 3500 Free and Total Residual Chlorine Monitors 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 monitors (including remote access to all control options) is available via the internet, and via a LAN. In fact the CRIUS^® 3500 chlorine analysers have all the options you could want in a Chlorine Analyser whilst maintaining a low cost and great value for money.

Chlorine Analyser Applications

• 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

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).

Chlorine sensor in overflow cell

Residual Chlorine Analyser Key Benefits

• Stable and reliable Residual Chlorine Monitor
• Free chlorine analysers
• Total chlorine analysers
• Combined chlorine analysers
• Bufferless chlorine monitors
• Reagentless chlorine monitors
• Low purchase cost
• Low cost of ownership
• Reduced pH dependency
• SMS text alarms
• Remote Access via Internet
• 4-20mA and relay Outputs
• Residual Chlorine Analyser

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