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pH Controllers Specifications

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Input / Control Channels




   Number of Inputs
 
     The number of inputs is the total number of signals sent to the controller. This number includes process variable signals such as temperature, pressure, level, speed, etc., and status inputs such as on/off.
 
   Search Logic:      All matching products will have a value greater than or equal to the specified value.
   Number of Control Outputs
 
     The number of control outputs is the total number of outputs used to control, compensate or correct the process. This number includes analog control outputs as well as relays and switches which activate or deactivate control devices.
 
   Search Logic:      All matching products will have a value greater than or equal to the specified value.
   Number of Zones (if applicable)
 
     The number of zones which the controller can monitor and maintain.
 
   Search Logic:      User may specify either, both, or neither of the "At Least" and "No More Than" values. Products returned as matches will meet all specified criteria.
   Controller Inputs:       
   Your choices are...
 
      
 
   DC Voltage Input
 
     Controllers accept analog DC voltage inputs such as ±5 V, 0 -10 V, etc.
 
   Current Loop (Transmitter) Input
 
     Current loop (transmitter) inputs include analog inputs such as 4 - 20 mA and 0 - 50 mA, or any other current-loop signal from a transmitter.
 
   Resistive / Potentiometer Input
 
     Controllers accept analog inputs from a resistor or potentiometer which monitors the process variable(s).
 
   Frequency Input
 
     A pulse or frequency input is used to measure and indicate a process variable for feedback to the controller.
 
   Switch / Relay Input
 
     Controllers accept a discrete, on/off voltage signal from a sensor or switch which monitors the process.
 
   Serial / Digital Input
 
     Controller inputs include signals in serial, parallel, Ethernet or other digital formats which indicate a process variable. This includes process measurement, but not communication lines.
 
   Network / Fieldbus Input
 
     Controllers accept commands and inputs from information converted to an industrial fieldbus protocol such as CANbus, PROFIBUS®, or SERCOS, or other industrial automation protocol. PROFIBUS is a registered trademark of PROFIBUS International.
 
   Other
 
     Other unlisted, specialized, or proprietary input signals.
 
   Search Logic:      All products with ANY of the selected attributes will be returned as matches. Leaving all boxes unchecked will not limit the search criteria for this question; products with all attribute options will be returned as matches.
   Control Signal Output:       
   Your choices are...
 
      
 
   Analog Voltage
 
     Controllers produce analog DC voltage outputs such as ±5 V, 0 - 10 V, etc.
 
   Current Loop
 
     Controllers produce a current loop output such as 0 - 20mA, 4 -20 mA, 10 - 50mA, etc.
 
   Switch / Relay Output
 
     The output is a switch or relay that can be "on" or "off".
 
   Pulse / Frequency
 
     The control output is an analog frequency value, a pulse train, or a similar variable.
 
   Serial / Digital
 
     Controller outputs include signals in serial, parallel, Ethernet or other digital formats which indicate a process variable. This includes process measurement, but not communication lines.
 
   Network / Fieldbus Output
 
     Controllers output information using an industrial fieldbus protocol such as CANbus, PROFIBUS®, SERCOS, or other industrial automation protocol. PROFIBUS is a registered trademark of PROFIBUS International.
 
   Other
 
     Other unlisted, specialized, or proprietary control signals.
 
   Search Logic:      All products with ANY of the selected attributes will be returned as matches. Leaving all boxes unchecked will not limit the search criteria for this question; products with all attribute options will be returned as matches.
Controller Type




   Control Technique       
   Your choices are...
 
      
 
   Limit / Set Point Control
 
     Limit control establishes set points or limits that, when reached, send a signal to stop or start a process variable. This "off-on" or "bang-bang" control is a fairly simple type of control.
 
   Linear Control
 
     Linear control matches a variable input signal with a correspondingly variable control signal. Signal conditioning, filtering, and amplification may occur to produce the proper output control signal.
 
   Feedforward Control
 
     Feedforward control is direct control compensation from the reference signal. This technique does not require a sensor. It may be open-loop or used in conjunction with more advanced PID control.
 
   PID Control
 
     Proportional, integral, and derivative (PID) control requires real-time system feedback. PID is a sophisticated control technique which monitors the error between a desired variable value and the actual value, and adjusts the control accordingly (proportional). Derivative and integral features can provide further control refinement by incorporating variables like rate-of-change of error to tune the control signal. Though sophisticated, PID controls must be tuned to prevent noisy operation and provide accurate process control.
 
   Fuzzy Logic
 
     Fuzzy logic is a type of logic in which variables can have imprecise values (as in partial truth) rather than a binary status (completely true or completely false). Information and rules can be inexact, and calculations can be made on these imprecise values.
 
   Advanced / Nonlinear Control
 
     Advanced or nonlinear controls include unlisted control algorithms such as neural networking, adaptive gain, or emerging algorithms.
 
   Other
 
     Other unlisted or specialized control algorithms or techniques.
 
   Search Logic:      All products with ANY of the selected attributes will be returned as matches. Leaving all boxes unchecked will not limit the search criteria for this question; products with all attribute options will be returned as matches.
   PLC Controller
 
     The device is a programmable logic controller (PLC).
 
   Search Logic:      "Required" and "Must Not Have" criteria limit returned matches as specified. Products with optional attributes will be returned for either choice.
   PC-Based Controller
 
     The controller is a circuit board that can be installed directly in a personal computer (PC).
 
   Search Logic:      "Required" and "Must Not Have" criteria limit returned matches as specified. Products with optional attributes will be returned for either choice.
   Multi-Function Controller
 
     The controller has multiple control modes or functions, which may or may not use different inputs and outputs. Different parameters or machines may be controlled by the same unit.
 
   Search Logic:      "Required" and "Must Not Have" criteria limit returned matches as specified. Products with optional attributes will be returned for either choice.
   Accuracy
 
     Accuracy signifies the closeness of the data to a specified target value.
 
   Search Logic:      All matching products will have a value less than or equal to the specified value.
   Special Capabilities (if required)       
   Your choices are...
 
      
 
   Laboratory Controller
 
     Laboratory controllers are designed specifically to monitor and/or control variables involved in laboratory or scientific experimentation, testing, or sample preparation. These devices often control temperature, and may also control other variables.
 
   pH / ORP Controller
 
     pH and ORP controllers monitor and can control the pH (acidity or alkalinity) and/or the oxidation reduction potential (ORP) of liquids involved in a testing or process application.
 
   Search Logic:      All products with ANY of the selected attributes will be returned as matches. Leaving all boxes unchecked will not limit the search criteria for this question; products with all attribute options will be returned as matches.
User Interface




   Form Factor       
   Your choices are...
 
      
 
   Circuit Board
 
     Devices are printed circuit boards (PCB) that can be attached to an enclosure or plugged directly into a computer backplane.
 
   Panel / Chassis Mount
 
     Devices attach to a panel or bolt onto a chassis, wall, cabinet, or enclosure.
 
   Rack Mount
 
     Devices mount in racks and come with hardware such as rail guides, flanges, or tabs. Some rack-mounted devices fit in a standard 19” telecommunications rack.
 
   DIN Rail
 
     Devices mount on a standard DIN rail. DIN is an acronym for Deutsches Institut für Normung (DIN), a German national organization for standardization.
 
   Stand-Alone
 
     Devices are benchtop or floor-standing units with a full casing or cabinet and an integral interface.
 
   Other
 
     Other unlisted form factors.
 
   Search Logic:      All products with ANY of the selected attributes will be returned as matches. Leaving all boxes unchecked will not limit the search criteria for this question; products with all attribute options will be returned as matches.
   User Interface       
   Your choices are...
 
      
 
   Knobs / Switches / Meter
 
     Adjustments are made with DIP switches, knobs, jumpers, and/or other simple settings.
 
   Digital Front Panel
 
     Devices are set up or programmed via a digital front panel with a keypad and displays, menus, and similar display functions.
 
   Computer Programmable
 
     Devices can be programmed and/or controlled remotely with a computer.
 
   Ethernet / Networkable
 
     Devices are designed to be part of a network, connected to other computers for the purposes of monitoring or control.
 
   Web Enabled
 
     Devices use hardware and software protocols such as hypertext transfer protocol (http) or web access protocol (WAP) in order to be addressable to, or a node of, the World Wide Web for remote monitoring or communication.
 
   Search Logic:      All products with ANY of the selected attributes will be returned as matches. Leaving all boxes unchecked will not limit the search criteria for this question; products with all attribute options will be returned as matches.
Specific Functionality




   General       
   Your choices are...
 
      
 
   Rate Indication / Control
 
     Devices monitor, indicate, and/or control the rate of the material or media.
 
   Totalizer
 
     Devices totalize the amount of material, media, or process variable.
 
   Datalogger
 
     Devices log systems or process variables and/or control commands for subsequent viewing or analysis.
 
   Chart Recorder
 
     Devices have chart recorder capabilities.
 
   Search Logic:      All products with ANY of the selected attributes will be returned as matches. Leaving all boxes unchecked will not limit the search criteria for this question; products with all attribute options will be returned as matches.
   Media       
   Your choices are...
 
      
 
   Liquid
 
     Devices control the flow, temperature, etc. of water.
 
   Solids / Powder
 
     Devices controls the flow or other property of solids, powders, grains, etc.
 
   Gas / Air
 
     Devices control the flow, temperature, pressure, etc. of a gas such as air, or specific gases.
 
   Steam
 
     Devices control the flow, temperature, pressure, etc. of steam.  Steam can be used for heating, cleaning, and other industrial applications.
 
   Other
 
     Other unlisted, specialized, or proprietary media.
 
   Search Logic:      All products with ANY of the selected attributes will be returned as matches. Leaving all boxes unchecked will not limit the search criteria for this question; products with all attribute options will be returned as matches.
Standards and Compliance




           
   Your choices are...
 
      
 
   RoHS Compliant
 
     Restriction of Hazardous Substances (RoHS) is a European Union (EU) directive that requires all manufacturers of electronic and electrical equipment sold in Europe to demonstrate that their products contain only minimal levels of the following hazardous substances: lead, mercury, cadmium, hexavalent chromium, polybrominated biphenyl and polybrominated diphenyl ether. RoHS will become effective on July 1, 2006.
 
   WEEE Compliant
 
     The Waste Electrical and Electronics Equipment Regulations (WEEE Regulations) is a European Parliament Directive with the aim of encouraging reuse, recycling and recovery of electrical and electronic equipment, and to improve the environmental impact and performance of these equipments.  This directive sets the requirements and criteria for the collection, treatment, recycling and recovery of these equipments. It makes producers responsible for financing these activities, and retailers and distributors must provide means for consumers to return used or obsolete equipments without charge.
 
   Other
 
     Other unlisted standards and compliances.
 
   Search Logic:      All products with ANY of the selected attributes will be returned as matches. Leaving all boxes unchecked will not limit the search criteria for this question; products with all attribute options will be returned as matches.
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