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lpha-2000 Series Process Controllers. lpha pH/ORP 2000 lpha CON 2000 lpha DO 2000. Eutech Instruments. FEATURES of lpha2000 Series. ASIC-based with intelligence and flexibility - matrix format programming User-selectable functions that can be customized to suit one’s requirements
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lpha-2000 Series Process Controllers lpha pH/ORP 2000 lpha CON 2000 lpha DO 2000 Eutech Instruments
FEATURES of lpha2000 Series • ASIC-based with intelligence and flexibility - matrix format programming • User-selectable functions that can be customized to suit one’s requirements • On-line push-button calibration • Built-in non-volatile memory backup
FEATURES of lpha2000 Series • Multi-level password protection - avoid unauthorized tampering of the system • Auto/Manual selection for control function • HOLD function • Proportional and Proportional Integral Control - Pulse length/Frequency
PROPORTIONAL VS PROPORTIONAL INTEGRAL AMPLIFIER PROCESS SETTING OUTPUT ERROR SIGNAL + - FEED BACK SUMMING ERROR SIGNAL + + - INTEGRATOR + PROCESS AMPLIFIER OUTPUT
PI CONTROL - ERROR CORRECTION PI Control P Control
FEATURES of lpha2000 Series • 14 segment LCD display • Backlit ‘Transflective’ LCD • Two current outputs • Choice of 0/20 or 4/20 mA • 22mA for ‘Out of Range’ condition • Push-button display of set points
FEATURES of lpha2000 Series • Zoomable transmitter output • Galvanically isolated signal output • Isolated 12V/50mA DC output • On/Off delay time for Set point relays • Set point Relay state programmable
FEATURES of lpha2000 Series • Hi/Lo feature for set-points • 4 Relays, 2 for Setpoints, Alarm and Wash • On-delay for Alarm relay • Hysteresis band -- prevent signal overshoot from false triggering & on/off continuously
HYSTERESIS RELAY ON RELAY OFF SP1 Set to LO SP2 set to HI 4 4.5 7 9.5 10 SP1 SP2 FORWARD DIRECTION REVERSE DIRECTION HYSTERESIS BAND ( DEFAULT 0.5 pH ) The controller relay activates when the set point is reached. In the reverse direction, it does not de-activate when the value reaches the set point. Instead, it continues to be active till the value reaches the amount set by the Hysteresis band.
FEATURES of lpha2000 Series • Choice of Pt100 or Pt1000 • Temperature in Centigrade or Fahrenheit • Two wire or three wire system • Choice of ATC or MTC -- independent Temp setting for Process and Calibration • Switched Mode power supply
FEATURES of lpha2000 Series • 80 to 250 V AC/DC auto detect • Detachable back panel connectors • Standard 144x144mm front panel • Protection against EMI with CE mark endorsed • IP 65/NEMA 4X rated field mount housing – W series
FEATURES of lpha-pH2000 Series • pH/ORP mode of operation, both in one controller • ORP mV or ORP % mode of operation • Symmetrical or Asymmetrical input • Choice of use with Glass or Antimony electrode
FEATURES of lpha-pH2000 Series • Auto buffer recognition - choice of 7 buffers • One point Cal choice of 7.00 or 6.86 pH • Electrode status display after calibration • On line offset adjustment for pH and Temp
CHARACTERISTIC CURVE OF CONTROLLER LIMIT CONTROLLER 100% 50% SP1 Xp= 0 SP2 Xp=0 PROPORTIONAL CONTROLLER 100% 50% Prop. Band Xp Prop. Band Xp
FEATURES of lpha-CON2000 • 2 cell or 4 cell operation • Wide range up to 1000 mS/cm • User selectable – 7 ranges • Cell constant input for automatic correction • Cell constant from 0.005 to 9.999
FEATURES of lpha-DO2000 • mg/l , ppm or % saturation mode of operation • Extended range 0 to 300%, 0 to 25 mg/l • Pressure compensation for the % sat. mode • Auto calibration in the % saturation mode • Choice of two cells: 0-10 or 0.5 - 40 ppm • Pressure input in mmHg and Kpa
Combined Electrode Pair Conventional Technique 100 MEG E1 E1 E2 E1- E2 E2 pH Glass Electrode pH Reference Electrode
Conventional Construction 100 MEG E1 E1- E2 E2 E2 E1 pH Reference Electrode pH Glass Electrode
Pitfalls of Conventional pH • Plugging junction • Poisoning of the internal element • Rapid electrolyte depletion • Ground loops
Combination Electrode Differential Electrodes Preamplifier Technique Comparison
Benefits of Differential pH • Reduced cost of ownership • Long life with glass reference electrode • Replaceable quad junction salt bridge • Buffered electrolyte (typically 7pH) • Long sensor to analyzer distances without coax • Low impedance reduces noise pickup • Ground rod eliminates ground loops • Adjustable isopotential point
7 pH Buffer Reference solution when using pH glass 0.05 Molar Potassium Phosphate, pH adjusted with NaOH Reference Electrode Solution Reference solution when using silver/silver chloride wire 4 Molar KCL with AgCL Reference Solutions Standard Combination pH Reference Differential pH Reference
Preamplifier Temperature Compensator Process Electrode (E1) Solution Ground Electrode (E3) Reference Electrode (E2) Differential Technique E1 - E3 -(E2 - E3) (E1 - E2)
Differential pH measurement • Two protected pH glass electrodes • Ground rod • Accurate temperature measurement • Up to 1000 foot cable • Very large reference chamber • Replaceable solution • Volume resists contamination • Any reference from 2 pH to 10 pH • Long-lasting salt bridge • Quad junction • Replaceable • Smooth surfaces reduce fouling.
1.5 Inch NPT threads Huge internal reference chamber Replaceable quad junction salt bridge Low profile pH glass Six wrench flats Short 6-inch body Ground rod Smooth surfaces reduce chance of fouling
Easy Replacement • O-Ring sealed • Quad Junction • Seals in sanitary fittings
Cutaway Reference Electrode Ground Rod Amplifier Reference Buffer Quad Junction Bridge Active Electrode O-ring seals
pH Sensor Care • Dehydration • Detrimental factors to electrode life • Abrasion • Coating • Temperature Shock • Transportation • Storage
Competition • GLI (Patent 3,709,796 and 3,862,895) • Rosemount • E + H • ATI • Aquametrics
Instumentation ? Alpha pH 2000D