Digital SMART SENCOM™ pH/ORP Sensor FU20F

All-In-One pH and ORP digital SMART sensor that keeps the motto "Simple is best" while combing the sensor with built-in intelligence and direct digital communication. The FU20F sensor features four separate elements (pH, reference, temperature, ORP) allowing for simultaneous measurement of pH and ORP is possible with one sensor in a rugged Ryton (FU20) body. The integral NPT threads on the sensor or the Quick Release Adapters make installation convenient and allow easy removal of the sensor for cleaning and calibration

  • Solid Platinum ORP/LE electrode for accurate simultaneous pH and ORP (REDOX) measurements
  • Integral Pt1000 element for enhanced pH accuracy
  • Extended life time by saturated Ag/AgCl reference system with double junction combined with ion-trap, and porous PTFE reference diaphragm
  • Extended life time by large volume of polymerized electrolyte and porous PTFE diaphragm
  • Simple maintenance by comprehensive design
  • Direct in-line, immersion or off-line installation
  • Calibration certificate delivered with each sensor
  • Available in two versions, a robust dome shape model for applications with a limited amount of solids, and a flat surface model for applications in which solids are a considerable component
  • Quick-Release adapter available
  • Easy setup by sensor specific characteristics stored in the sensor itself
  • Available in two versions, a robust dome shape model for applications with a limited amount of solids, and a flat surface model for applications in which solids are a considerable component
  • CE, ATEX, CSA and FM Approval. However *Can only be used General Purpose at this time, because FLXA21 SENCOM™ module and SPS24 Interface box are pending ICECx, ATEX, FM and CSA approval*

WU11 Connection Cable

The WU11 interconnection cable is specified for reliable transfer of digital signals between the SENCOM sensors and Yokogawa FLXA™ analyzer. It is espically designed to be installed in a heavy industrial environment. The cable is water proof, IP67, allowing it to be submerged as a whole. The cable has a wide temperature operation range which is sufficient for most of the applications. The materials used for the cable are flame retardant to resist the spread of fire.

  • Double shielding to protect connected devices for interference from high voltages and currents
  • Available in four different lengths. Long cable runs up to 100 m (328 ft) are possible
  • Easy connection to a SENCOM pH Sensor by one 5- pins molded connector, and to the analyzer by 5 wired pins
  • Flame retardant recognized by UL (fileno. E124763) and CSA (fileno. LL105324)
  • IP67
  • Operating temperature from - 40ºC up to + 85°C (-40ºF up to +185°F)

Wet scrubbers are used in utilities, paper mills, and chemical plants to remove sulfur dioxide (SO2) and other pollutants from gas streams. Undesirable pollutants are removed by contacting the gases with an aqueous solution or slurry containing a sorbent. The most common sorbents are lime, Ca(OH)2, and limestone, CaCO3


For control of batch neutralization, a pH measurement coupled with a timer-controlled chemical feed scheme provides very satisfactory results.

This system can be adapted for either acid waste or alkaline waste neutralization.


There are a number of suppliers of oil and fat products used for edible purposes. These products include, but are not limited to olive oil, peanut oil, soybean oil, sunflower oil, lard, shortening, butter, and margarine. The raw materials for these products include animal by-products, fleshy fruits (palm and olive), and oilseeds. 

Industry:Food and Beverage


Process liquid analyzers such as pH meters, conductivity meters, ORP meters, and density meters play an important role at electrolysis plants in the control of concentrations of various process solutions. This requires both precision and stability under harsh conditions that include highly corrosive substances, high temperatures, and many impurities.


Most zinc are produced at hydrometallurgically, where a high-grade zinc product can be obtained and valuable metals mixed in the raw material can be recovered. In the hydrometallurgy, the raw material of zinc concentrate is roasted and then dissolved in sulfuric acid to remove impurities. The process called leaching and pH control of the leachate is important.

Industry:Chemical, Power


Wastewater from electroplating facilities and certain types of chemical plants contains toxic forms of hexavalent chromium such as chromate and dichromate. The hexavalent chromium in this wastewater must be reduced before the water can be discharged. This requires a two-step process: hexavalent chromium (CR6) is reduced to trivalent chromium (CR3); and CR3 is precipitated as chromium hydroxide.

Industry:Electrical and Electronics


Removal of free oil and grease from a wastewater stream reduces the potential for equipment problems to occur further downstream. There are three forms of oil encountered in wastewater treatment at a refinery. 


Cyanide-bearing wastewater from mining and electroplating facilities and certain types of chemical plants is toxic and must be treated by oxidation with chlorine or chloride to bring the cyanide concentration within regulatory limits.

Industry:Electrical and Electronics


Fish perform all their bodily functions in water. Because fish are totally dependent upon water to breathe, feed and grow, excrete wastes, maintain a salt balance, and reproduce, understanding the physical and chemical qualities of water is critical to successful aquaculture. To a great extent water determines the success or failure of an aquaculture operation.



The Combined Effects of pH and Percent Methanol on the HPLC Separation of Benzoic Acid and Phenol:

Many mobile-phase variables can affect an HPLC (High Performance Liquid Chromatograph) separation. Among these are pH and the percent and type of organic modifier. The pKa of a weak acid is the pH at which the acid is equally distributed between its protonated (uncharged) and unprotonated (charged) forms. This is illustrated by the Henderson–Hasselbalch equation:

pH = pKa + log ([A_]/[HA]

where [A_] is the concentration of the weak acid in its unprotonated form
and [HA] is the concentration of the weak acid in its protonated form.

If the weak acid is equally distributed between its two forms, ([A_]/[HA]) = 1, log ([A_]/[HA]) = 0, and pH = pKa. If the weak acid is not equally distributed between its two forms, then the pH will be either less or greater than the pKa of the weak acid.

For example, if [A_] < [HA], ([A_]/[HA]) < 1, log ([A_]/[HA]) < 0, and pH < pKa. Thus, a weak acid exists primarily in its protonated form at a pH below the pKa and therefore has a greater affinity for the nonpolar stationary phase. If [A_] > [HA], ([A_]/[HA]) > 1, log ([A_]/[HA]) > 0, and pH > pKa. Thus, a weak acid exists primarily in its unprotonated form at a pH above the pKa and therefore has a greater affinity for the polar mobile phase.

Fig 1 - full-factorial experimental design

Fig. 1 - A three-level, two-factor
full-factorial experimental design

Organic modifiers also have an effect on the retention of solutes in HPLC. In the reversed-phase mode (polar mobile phase, nonpolar stationary phase), the most polar solute component will elute first. This is because the most polar component interacts least with the nonpolar stationary phase.

As the polarity of the mobile phase is increased, those solute components that were previously highly retained (nonpolar components) will be retained even more.

Two species that are of public interest because of their classification as moderate environmental and health hazards are benzoic acid (pKa = 4.202) and phenol (pKa = 9.98). The purpose of this study is to investigate the combined effects of pH and percent methanol on the reversed-phase HPLC separation of these compounds.

A three-level, two-factor fullfactorial experimental design will be used to specify nine mobile phases for consideration in this study. The levels of pH were chosen to bracket the pKa value of benzoic acid (below, near,
and above 4.202). It was not possible to study a mobile phase with a pH > 7.5 owing to the pH range limit of the column. A methanol/water mobile phase was selected for this study because methanol is readily available in most undergraduate labs and relatively inexpensive. In addition, both solutes elute in a relatively short time, making completion of this lab during one or two lab periods possible.

Table 1. Mobile Phases Specified by the Experimental Design
Phase No. Methanol % pH
1 25 3.0
2 25 4.5
3 25 6.0
4 50 3.0
5 50 4.5
6 50 6.0
7 75 3.0
8 75 4.5
9 75 6.0

Major Observation

At low mobile-phase methanol concentration (25%), as pH increases, the retention time of phenol appears to be unaffected, whereas the retention time of benzoic acid decreases significantly. Over the pH range investigated, the mobile-phase pH is below the pKa of phenol. Thus, phenol will remain in its protonated form and should be unaffected by these mobile-phase changes. However, as pH increases, benzoic acid shifts from its protonated to its unprotonated form, decreasing its affinity for the nonpolar stationary phase and decreasing its retention time.

At intermediate (50%) and high (75%) mobile-phase methanol concentrations, as pH increases, the retention time of phenol remains unaffected by increases in pH while the retention time of benzoic acid decreases. This is consistent with the behaviour at low methanol concentration.

At pH 3.0, as percent methanol increases, the retention times of both phenol and benzoic acid decrease significantly. Because both solutes are polar, increasing mobile-phase polarity causes both to be retained less tightly. At pH 4.5 (slightly above the pKa of benzoic acid) and pH 6.0 (well above the pKa of benzoic acid) as percent methanol increases, the retention times of phenol and benzoic acid decrease. This is consistent with the retention behaviour at pH 3.0.

Typical Process Details

  • Customer plant: Bulk drug plant
  • Application: This is 4 cycle application. There will 
be a pipe connected to inlet which allows process to flow through the column and the same will be sent out from another pipe at outlet.
  • pH measurement is typically required at both the inlet and outlet. Temp: 30-40°C. pH range shall be 7 to 7.5. Between this range the customer can take necessary action to control his process.
  • Conductivity max. 300 micro siemens/cm.
  • Cycle 1: Process contains 95% liquid methanol, 
2% liquid ammonia, 3% water.
  • Cycle 2: Process contains 30% liquid methanol, 
70% water.
  • Cycle 3: Process contains 90% liquid methanol, 
5% liquid ammonia, 3% water, 2% sugar content.
  • Cycle 4: The column will be cleaned by flushing 
with DM water.

The term "cooling tower" is used to describe both direct (open circuit) and indirect (closed circuit) heat rejection equipment. Cooling towers are heat-transfer units, used to remove heat from any water-cooled system. The cooled water is then re-circulated (and thus, recycled) back into the system. Since the process water is re-circulated, the mineral concentration increases as a result of the evaporation.

Industry:Refining, Food and Beverage, Power, Oil and Gas, Pulp and Paper, Chemical


The lifetime of a pH sensor has a significant impact on the overall annual costs of a pH measuring loop. Optimizing four key factors will decrease these costs and optimize process control and overall plant efficiency.