Turtle Tough TT-ISE-CL2, Руководство пользователя

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TURTLE
TOUGH
®
5

 analyser 
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The Turtle Tough model TT-ISE-CL2 use s a membrane covered amperometric sensor to.
continuously monitor and control free or total residual chlorine without any reagents or moving parts.
The difference between the two models is the type of sensor used and corresponding measurement it
produces, free or total chlorine. The analyser interface is the same for both sensor types except for
the available operating ranges for each sensor type.
The measurement system does not alter the sample and does not add chemicals to the sample
stream.
 TT-ISE-CL2 
  
Wastewater that has undergone tertiary treatment may be possible to monitor if final water product is
at or near drinking water standards.
For the measuring methods used here, chlorine diffuses through the membrane from the
measurement medium and, combined with the electrolytes, triggers an electrical signal at the working
electrode. This signal is proportional to the concentration of chlorine and is amplified by the
electronics. The measurement signal is independent of the temperature of the media due to an
integrated temperature compensation.
pH has an effect on chlorine measurement accuracy since the sensor measures only the
hypochlorous acid (HOCl) form of chlorine, and not the hypochlorite ion (OCl
-
) form of chlorine. The
ratio of these two different types of chlorine varies with the pH value of the analyte. This behavior is
described by the hypochlorous acid dissociation curve. In the 3-electrode sensor there is a linear loss
of slope, or decrease in residual value, of about 5% for every 1 pH unit increase after pH 7. In the 2-
electrode sensor there is a 65% loss of slope at pH 8.
The sensor is not intended or recommended to measure or ensure the absence of chlorine.
The sensor is not suitable for determining organic chlorination agents such as cyanuric acid based
products.
The sensor cannot distinguish between various species of chloramines.
The analyser requires a constant and consistent sample flow at no more than atmospheric pressure
as well as a waste drain.
The monitoring of reservoirs, basins or tanks requires a pump to deliver sample to the analyser at the
required pressure and flow rate. Intermittent operation is possible within certain time limitations.
Residual measurements are determined and output continuously, the analyser does not use a sample
and hold method for residual determination.
The microprocessor based electronics are designed with additional capacity to accept both software
and hardware upgrades so that the analyser can be converted over time into a multi-function and
multi-parameter measurement system.