720 Series II pH & ORP MONITOR/CONTROLLER Operation Manual 10 August 11 INSTALLATION • OPERATION • MAINTENANCE pH Models: 721II, 722II, 723II & 724II ORP Models: 726II, 727II, 728II & 729II ACCURACY • RELIABILITY• SIMPLICITY Water Quality Instrumentation Accuracy • Reliability • Simplicity
720 Series II MONITOR/CONTROLLER QUICK REFERENCE GUIDE! If you read nothing else in this manual please read this Quick Reference Guide. PLEASE READ and COMPREHEND ALL WARNINGS, CAUTIONS and ADVISEMENTS CONTAINED WITHIN THIS MANUAL. Failure to comply is beyond the responsibility of the Myron L Company. WARNING: ALL MONITOR/CONTROLLERS ARE FACTORY SET TO OPERATE ON 115 VAC. BEFORE APPLYING POWER ENSURE THE INPUT POWER “115/230 VAC” SELECTION IS CORRECT FOR YOUR REQUIREMENTS.
3. Press and hold the “SET POINT” switch on the front panel. Using a tweaker or a small screwdriver, adjust the Set Point trimmer adjustment screw on the circuit board to sweep the display from zero to full scale. (A digital display may be blank at the full scale end. This is normal.) Listen for the alarm relay to click on and off as the alarm set point moves past the water reading. 4. Adjust the alarm to the desired set point value. Release the “SET POINT” switch.
pH 720II MYRON L COMPANY HIGH SET POINT LOW 720 Series II Model 723II-SC (A Digital pH Monitor/controller, with a Second Alarm/Control) 1
TABLE OF CONTENTS SECTION PAGE 720 Series II ILLUSTRATION (723II-SC) 1 I. INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 A. SCOPE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 1. Functional Descriptions . . . . . . . . . .
TABLE OF CONTENTS Continued SECTION PAGE 3. Recalibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 4. Converting a Current to a Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 C. TP/TPO MODULE (TEMPERATURE OPTION) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
TABLE OF CONTENTS Continued SECTION VI. VII. VIII. IX. X. XI. 4 PAGE OPTIONS & ACCESSORIES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52 A. OPTIONS ORDERED WITH MONITOR/CONTROLLER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52 B. OPTIONS & ACCESSORIES ORDERED SEPARATELY . . . . . . . . . . . . . . . . . . . .
I. INTRODUCTION Thank you for selecting one of the Myron L Company’s new 720 Series II Monitor/controllers. The 720 Series II is based on input from ‘you’ - our customers, time proven designs, and many years of instrumentation experience. Since 1957, the Myron L Company has been providing customers with quality products at an affordable price by designing and producing products that are Accurate, Reliable, Simple to use. Quality you have come to rely and depend on.
LINEARITY Electronics: ±0.05% (±0.01pH units / ±1mV of full scale) RESOLUTION Digital Display: ±0.01 pH units / ±1mV Analog Meter: ±0.13pH units / ±40mV SENSITIVITY 0.05 % of full scale (0.01pH units / 1mV) STABILITY ±0.05 % of full scale (±0.01pH units / ±1mV) REPEATABILITY ±0.05 % of full scale (±0.01pH units / ±1mV) CALIBRATION CHECK Built in (7 & 0 pH / 0 & -2000mV) RECORDER OUTPUT Isolated 0-10 VDC @ 5mA max.
E. SENSORS 1. pH 720 series II pH Monitor/controllers use the P72 series sensors. Its compact size allows mounting in a standard 1/2” or 3/4” MNPT fitting or tee depending on model. 2. ORP 720 series II ORP Monitor/controllers use the O72 series sensors. Its compact size allows mounting in a standard 1/2” or 3/4” MNPT fitting or tee depending on model. For detailed descriptions of these and other sensors, see pH/ORP Sensor Selection Guide. 3.
G. 720 Series II Configuration Guide pH & ORP pH requires P7XX series sensor ORP requires 07XX series sensor 721II, 722II, 723II & 724II 726II, 727II, 728II & 729II Configuration pH ORP pH (Analog & Digital) CMpH ORP Digital CMORPD ORP Analog CMORPA pH/ORP Sensor Part Numbers Part Number Description: First Location = Sensor type, i.e.
II. INSTALLATION A. the four (4) additional screws/bolts to mount the SMP to the wall or fixture. Their size is to be determined by the user. GENERAL 1. 2. 3. 4. This section provides the recommended procedures for properly installing the 720 Series II pH/ORP Monitor/controller, and sensors. For OEM models see section II.C.
4. Slide the enclosure through the panel cutout until its flange contacts the panel. 5. Insert mounting screws through the flange mounting holes and tightly secure. 6. Reconnect all panel cable(s)/wires and re secure the front panel using 6-32 x 3/8” screws provided. Caution: Do not use 6-32 x 1/2” used on “picture frame” front panel models. .125 X4 (3.125) 1.880 (47.75) 2.218 Dia. 56.34 C.
1. INSERTION MODE (in-line installation) Use one of the following as a guide. The Heavy Duty pH or ORP sensor may be installed in any direction including inverted (sensor UP). Substitute ORP sensor for pH where applicable. Use approved sealant, i.e. Teflon tape as required. 1. Insert the Sensor Fitting assembly into the “T” fitting as shown in one of the figures below. 2. Tightly secure. 2. IMMERSION OR DIP SENSOR ASSEMBLY Use approved sealant, i.e. Teflon tape as required. 1.
E. ELECTRICAL INSTALLATION The electrical installation procedures provided in this manual are common to all pH & ORP Monitor/controllers. See figure II.B.1 for the hole dimensions of the enclosure’s cable access holes. Unless otherwise instructed, refer to figure II.E.1. for the 720 Series II Monitor’s terminal block connector wiring designations. NOTE: After removing an enclosure’s access hole plug, it is suggested that the user mount a watertight restraint fixture prior to installing a cable.
! CAUTION - READ FOLLOWING CAREFULLY WARNING: BEFORE STARTING, IF MONITOR/ CONTROLLER IS INSTALLED, ENSURE THE POWER IS OFF. FAILURE TO DO SO COULD CAUSE DAMAGE TO THE INSTRUMENT, AND COULD BE HARMFUL OR FATAL TO PERSONNEL. ONLY QUALIFIED PERSONNEL SHOULD INSTALL OR SERVICE ELECTRICAL EQUIPMENT. NOTE: When opening instrument, remove front cover with care; a ribbon cable connects the front panel and main board. If the front panel has all ready been removed from the enclosure skip to #4. 1. 2. 3.
controller set point until the alarm/piezo sounds off. If controller is not yet connected to a functioning sensor, it may be necessary to press and hold the ZERO test switch. The black button on the front of the RA will mute the piezo alarm for approximately three minutes or until you improve the water quality (readjust controller set point). The piezo alarm will continue to sound off every three minutes until the user has improved the alarm condition inside the controller.
1. 2. Grasp connector and align wires DOWN on display or with the small edge of the display as shown in figure II.E.5. Press connector onto display pins. Ensure pins are aligned or they may become bent. Wiggle connector slightly “end to end” if necessary. DISPLAY DISPLAY CONNECTION DISPLAY HARNESS PANEL MOUNTED DISPLAY Figure II.E.5 F.
pH14 ORP2A ANALOG Module† ORP2D DIGITAL Module† NOTE: Some OEM models may not be re-configured being originally manufactured with fixed resistors. If your application requires re-configuring an OEM model, first contact the system manufacture for help. The Myron L Company may re-configure or exchange your instrument at a cost.
3. CHANGING ANALOG METER SCALE (DIAL) After changing configurations (pH to ORP or visa versa) on an analog model 720II it will be necessary to change the meter scale (dial). The following steps will guide you through the change. Please read caution carefully. ! CAUTION - READ FOLLOWING CAREFULLY 5. Using a 1/8” (3.2mm) hex driver, remove the two (2) small screws holding the scale (dial). See figure II.G.5. To remove the scale, lightly press on bottom of scale, the top will lift up.
UP Reverse the above procedure using the new scale. } UP Bottom View ORPA O ORP “ANALOG” CONFIGURATION MODULE Figure II.G.8 ORPA O ORPD O UP CENTER Zero Adjust (ZA) PIN PIN #10 ANALOG REMOVED Top View } NOTE: While replacing the clear plastic cover, ensure the ZA screw pin on the cover aligns with the inverted “Y” shaped slot on the meter movement. See figure II.G.5. IF, the inverted “Y” shaped slot is inadvertently moved BEFORE installing cover: a.
III. OPTIONS & ACCESSORIES A. SC/SCO MODULE (SECOND ALARM/CONTROL OPTION) (Digital & OEM Models ONLY) -SC SCO Second Alarm Control Module ordered with Monitor/controller. Second Alarm Control Module Kit ordered separately. 1. DESCRIPTION: An essential component for applications requiring a DUAL setpoint. The Second Alarm/control module allows the user additional flexibility by being able to sound TWO Alarms, and Control TWO functions with the second 10 amp relay.
Front Panel WARNING: there are two (2) O-rings installed on the switches, one (1) on the shank and the other is under the push button. Both of these O-rings must be reinstalled to maintain IP65/NEMA 4X ratings. See figure III.A.3. 7. 8. 9. 10. 1-4 assumes this is a conversion from a single alarm/control. Skip to #5 if new installation or assembly. 1. Carefully remove the RED LED from the front panel by pulling lightly on the wires.
The following instructions describe the steps for converting the Monitor/controller. Refer to figure III.A.4 for the location of the SPC(s) on your Monitor/controller. If unnecessary, skip to Set Point Adjustment. 3. 4. 5. 6. Ensure power is OFF. Locate the SPC jumpers for the alarm to be configured, see figure III.A.4. Make a note of the current orientation of the SPC jumpers. Remove both jumpers. This is easily done by hand. Take care not to crush the jumpers if using pliers.
c. Hysteresis (Dead Band) Adjustment* The hysteresis or dead band is approximately ±3% of the set point at full scale as it leaves the factory. Under normal (most) conditions it will not be necessary to adjust. However, if you desire to make an adjustment please keep the following in mind. The adjustment is very simple and is based on set point location. If the set point* is in the upper 75-100% of the scale, the hysteresis control pot should be turned fully to the right.
B. 4A/4AO MODULE (4-20mA OPTION) Available only on the digital models 728II, 729II, 723II and 724II, or analog and digital OEM. -4A 4AO 4-20mA Self/Remote-powered Isolated output module ordered with Monitor/controller. 4-20mA Self/Remote-powered Isolated output module ordered separately (includes harness). 1. DESCRIPTION The 4-20mA option gives the Series II Monitor/controller the ability to send a signal very long distances with minimal interferences and signal degradation.
FATAL TO PERSONNEL EQUIPMENT. PERSONNEL. ONLY SHOULD INSTALL QUALIFIED ELECTRICAL Physical If the front panel has all ready been removed from the enclosure skip to #3. 1. 2. 3. 4. Using a standard slot screwdriver remove the screws on the front panel. Carefully wiggle the front panel to loosen the gasket and pull gently toward you. Do not pull more than about 8 inches/20CM or you could damage the wiring harness. Turn the front panel around so that the back side is facing you.
SENSOR 7 pH/ZERO mV PUSH TO TEST SPAN (GAIN) PUSH TO TEST 5. 0-10VDC SPAN 6. ZERO SP1 HYS1 ORP ZERO CONFIGURATION MODULE 721 722 723 724 726 727 728 729 DIS 11. 12. 13. REMOVE TO INSTALL MYRON L COMPANY PWR CHS C GD NC NO CM CHS FUSE* PA RA TRANSFORMER 115/ 230 8. 9. 10. DEC REMOVE TO INSTALL SECOND RELAY ORP SPC INC 4-20 CONNECTOR CONNECT 4AO HARNESS HERE GND } ZERO SPAN UP 7. DEC } ORP DO NOT ADJUST SPAN BK WT RD GN NU R- R+ 3S 3. 4.
4. CONVERTING A CURRENT TO A VOLTAGE Current measuring devices actually measure voltage, but have an internal resistor as shown in figures III.B.1 & III.B.2 and are scaled to display in current. If you have a voltage device and you wish to utilize the current from the 4A (4-20mA) Module, the following will help you to make this conversion.
C. TEMPERATURE MODULE (Digital Models only) -TP Temperature Module ordered with Monitor/controller. TPO Temperature Module ordered separately includes label # LTEMP. Requires; Separate three (3) wire 1000Ω RTD temperature sensor. NOTE: OEM models require an additional display harness, part number TPMH. See OEM Installation. 1. DESCRIPTION The Temperature Module (TPO) gives the Monitor/controller more flexibility for the user by being in the same package.
5. 6. 7. 8. Set front panel down or carefully allow to hang from the harness. Do not drop as the harness connector will pull out allowing the front panel to fall. While holding the display and the plastic display retainer plate, carefully remove the display harness connector. Do not drop the display. Remove and discard the plastic display retainer plate. Insert display connector pins into the Temperature Module female connector. See figure III.C.1. 9.
CAUTION: The sensor input and 0-10VDC output connectors require only a small screwdriver or a pen to push on the release levers. The release levers may be broken or damaged if not pushed straight toward the CB. DO NOT push the release levers sideways. Figure III.C.5 TPC Module PRESS BUTTON FOR 199.9ºC/5.0VDC MYRON L COMPANY 0-5VDC + OUTPUT ORANGE BLUE BROWN BLUE BROWN Press TPC Module into TPO connector as shown. - + 0.0 DV Connect DVM leads as shown. BR BL OR - + Figure III.C.
19. Continue or reinstall the front panel and tightly secure retaining screws, see REASSEMBLY, page 31. CAUTION: The sensor input and 0-5VDC output connectors require only a small screwdriver or a pen to push on the release levers. The release levers may be broken or damaged if not pushed straight toward the CB. DO NOT push the release levers sideways. 1000.0Ω RESISTOR - + JUMPER 0.0 DV Connect DVM leads as shown. BR BL OR - + Figure III.C.8 1758.56Ω RESISTOR - + JUMPER 5.
3. 4. 5. 6. b. Temperature Set Point Adjust Ensure power OFF. Ensure the SCO Module Set Point control is set to FULL counter clockwise position. If not, turn SCO Set Point control fully CCW - it may be 30 turns - or until it clicks. For location see figure III.C.13. Turn power ON. Press BOTH the Temperature Select switch and the Set Point switch on the front panel. Adjust the TP/TPO Module Set Point Two (SP2) to temperature as desired. See figure III.C.1. Turn power OFF. c.
5. OEM INSTALLATION An OEM installation requires an additional display harness, part number TPMH. This harness is installed between the Temperature Module and the panel display as shown in figure III.C.14. Both connectors must be installed with the wires down or toward the bottom of the circuit board.
6. OEM INSTALLATION b. Dual Display Models SPECIAL ORDER These models allow simultaneous display of both Cond/TDS, RES or pH/ORP and Temperature. They require two display harnesses. The Cond/TDS, RES or pH/ORP display harness is part number DH2DD without control feature, or part number DHDD with control feature. The Temperature display harness is part number TPMH.
-TH THO Controller wiring Harness (requires second alarm/control module) ordered with Monitor/controller. Controller wiring Harness (requires second alarm/control module) ordered separately. 1. DESCRIPTION The optional TH/THO Controller Kit adds more flexibility to the Temperature Module by adding the ability to Alarm and/or Control using the 24VDC solid state output to drive a PA - Piezo electric alarm, and/or a 10 amp relay to operate a heater or chiller as required. a.
by pulling lightly on the wires. It may be necessary to use a small flat screwdriver to slightly spread the retaining ring. See figure III.D.1. b. Remove Set Point Switch from the front panel, figure III.D.1, by rotating the round bezel nut CCW on the front as shown in figure III.D.2. c. Remove SCH harness from SC Module by on pulling harness. d. Set SCH harness aside, it is no longer used. 4.
4. front as shown in figure III.D.2. Remove harness from SCO Module by pulling on harness, see figure III.D.3. d. Set SCH harness aside, it is no longer used. Remove SPC jumpers (2) from SC/SCO Second Alarm/Control Module, see figure III.D.3 for SPC jumper location. INSTALL THO HARNESS BLACK CONNECTOR HERE PA c.
SP2 HYS2 DIS ZERO FS DEC DEC SPC TP/TPO - TEMPERATURE MODULE TEMP CONTROL HARNESS DISPLAY 720 II TEMPERATURE TEMPERATURE TEMPERATURE LABEL LOCATION HIGH SET POINT TEMPERATURE REMOVE SC/SCO SET POINT SWITCH and RED LED DISPLAY CONNECTION Figure III.D.10 Turn SCO Set Point control fully counter clockwise - it may be 30 turns - until it clicks. See figure III.D.7 for location. 9. Locate and remove JUMPER from option to the TPO Module as shown in figure III.D.5. 10.
FOR TEMPERATURE MODULE Temperature Set Point Adjust 1. Ensure the SCO Module Set Point control is set to FULL CCW position. For location see figure III.D.7. 2. Press BOTH the Temperature Select switch and the Set Point switch on the front panel. 3. Adjust the TP/TPO Module Set Point Two (SP2) to temperature as desired. See figure III.D.9. SPC SET POINT CONVERSION (SPC) TEMP CONTROL HARNESS DETAIL OF SET POINT CONVERSION (SPC) ON TP/TPO MODULE AS CONFIGURED WHEN SHIPPED FROM THE MFR. Figure III.D.
E. DUAL TEMPERATURE MODULE & 4-20mA OUTPUT MODULE (Digital and OEM Models ONLY) -TP/TPO Temperature Module. -4A/4AO 4-20mA Self/Remote-powered Isolated output module. 1. DESCRIPTION The following instructions describe how install BOTH the 4A/4AO and the TP/TPO Modules to a Digital model Monitor/controller. Specifications See individual Data Sheets and installation instructions. SCREWS 4A/4AO PLASTIC SPACERS (4) TP/TPO Requires Plastic Spacers P# SP4819. 2.
F. PIEZO ELECTRIC ALARM -PA Piezo Electric Alarm ordered with Digital Monitor/controller. PAO Piezo Electric Alarm ordered separately for Digital or remotely mounted Analog Monitor/controller or OEM models. 1. DESCRIPTION The PA/PAO is an electronic sound device capable of emitting a 80dB or more @ 30cm, high pitched squeal. See figure III.F.1. Specifications Oscillating Frequency — 3.0≠0.5KHz Operating Voltage (750II) — 24VDC Nom. (1.5-30VDC Max.
REASSEMBLY Before reassembly, ensure set point control is set to desired trip point. 1. Carefully reinstall the front panel, bottom first. Ensure no wires have been pinched between enclosure and front panel. 2. Reinstall the screws and tighten. 3. To operate, turn power ON. SET POINT #1 CONTROL 7 pH/ZERO mV PUSH TO TEST SET POINT #1 HYSTERESIS RIGHT INC LEFT DEC 3S Red LED(s) FRONT PANEL Rear View Figure III.F.
G. REMOTE ALARM - RA™ RA Ordered as an accessory, includes 8” harness with connector, and two (2) wire nuts. 1. DESCRIPTION This remotely mounted AUDIBLE and VISUAL alarm connects to any Myron L Company Monitor/controller, or brand “X” controller with dry contacts. When activated by the controller the Remote Alarm will provide both an audible and a visual alert at a location other than at the controller.
10. If three minutes is too long or too short, adjust control inside RA until desired mute time is achieved (adjustable from approximately 15 seconds to 10 minutes). see figure III.G.1. 11. Replace the bottom of the RA, and secure to surface you have selected for its installation. 12. Carefully reinstall the controller front panel, bottom first. Ensure no wires have been pinched between enclosure and front panel. 13. Reinstall the screws and tighten. 14. To operate, turn power ON.
IV. OPERATING PROCEDURES A. Digital pH Monitor/controller with optional Dual Alarm/controls, and Temperature with control function, and Front Panel Test Switch. FRONT PANEL The front panel illustrations to the right, switch and indicator operational descriptions have been provided to assist the user in identifying and operating the 720 Series II Monitor/controllers. For OEM models see Section B. Refer to Section IV.C for Setup procedures and Section IV.D for Check-Out procedures. pH 720II 3.
B. OEM FRONT PANEL INDICATORS & CONTROLS The simulated OEM front panel illustrations to the right, and switch and indicator operational descriptions have been provided to assist the OEM user in identifying and operating the 720 Series II Monitor/controllers. Refer to Section V.C. for Setup procedures, and Section V.D. for Check-Out procedures. Digital pH Monitor/controller with optional Dual Alarm/controls, and Temperature with control function, and Front Panel Test Switch.
! CAUTION - READ FOLLOWING CAREFULLY C. SETUP PROCEDURES These Setup procedures cover (1) converting the alarm circuit to trigger on a decreasing or increasing reading, (2) checking out your new Monitor/controller, (3) setting the alarm circuit set point(s), and (4) adjusting the hysteresis. The following require that the front panel be removed. While doing so be careful not to strain the cable(s). NOTE: A small screwdriver or tweaker will be required for several of the following operations. 1.
REASSEMBLY 1. Carefully reinstall the front panel, bottom first. Ensure no wires have been pinched between enclosure and front panel. 2. Reinstall the screws and tighten. 3. To operate, turn power ON.
V. Component identification, Calibration and preventive care A. PRIMARY COMPONENT IDENTIFICATION As identified in Section III, the Monitors/controllers switch(es) and indicator components are mounted directly to the front panel. The Monitor/controllers main circuit board is contained within and mounted to the back of the enclosure. Some models with options have an additional circuit board mounted behind the front panel, i.e. Model 723II-4A (4-20 Module). Review figure V.A.
! CAUTION - READ FOLLOWING CAREFULLY B. METER MECHANICAL ZERO PROCEDURES ANALOG METERS ONLY 1. Ensure power is OFF. 2. Note the position of the meter needle. If it has come to rest pointing at the zero mark on the scale, turn the Monitor back ON and continue on to Section V.C. 3. Locate the small (approx. 1/4”), black plastic button directly below the center of the meter. Use a small screwdriver or a fingernail to gently pry it loose and remove it from the access hole. See figure II.G.9. 4.
3. CALIBRATION USING BUFFER SOLUTIONS The BEST method of calibrating your pH or ORP Monitor/controller is with NIST traceable Buffer Solutions (available from the Myron L Company). Because it includes the sensor, the entire system is calibrated. For ORP, use 7pH buffer solution to set 0mV. Where 4 or 10 buffer is referenced substitute ORP solution, or use the internal -1999mV calibration. 1. 2. 3. 4. 5. 6. 7. 8. 9.
5. TRANSFER STANDARD METHOD Another method of calibrating a Monitor/controller is via the transfer standard. Instead of removing the entire Monitor/ controller and sensor, and either returning it to the manufacture or sending it to a third party laboratory for recertification, the transfer standard allows for a quick check and return to service — less down time. It is very easy to perform, and may be used to check ANY manufactures Monitor/controller — pH or ORP.
VI. OPTIONS & ACCESSORIES A. OPTIONS ORDERED WITH MONITOR/CONTROLLER PART # DESCRIPTION -SC -4A -PA -TP -TH -PC Second Alarm/control Module 4-20mA Self-Powered Isolated Output Module (Digital & OEM Only) Piezo Electric Alarm Temperature Module 0-200°C, Requires Temperature Sensor (Digital & OEM Only) Alarm/control Harness Kit (Requires -SC & -TP) Powercord 115VAC (8 ft. with USA plug and Strain Relief) - NOT for 230VAC use.
C. STANDARD SOLUTIONS & BUFFERS 1. pH and ORP BUFFER SOLUTIONS Your pH and/or ORP Monitor/controller has been factory certified to meet certain specifications based on the appropriate Myron L Company NIST traceable buffer solutions. These same solutions are available to you. NOTE: ORP ZERO is calibrated using 7pH buffer. SPAN may be wet calibrated using any high quality ORP mV solution. These same buffers may be used for calibration and recertification of your Myron L or other handheld instruments.
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VIII. WARRANTY All Myron L Company pH and ORP Monitor/controllers have a TWO-year warranty. If any Monitor/controller fails to function normally, return the faulty unit to the factory prepaid. If, in the opinion of the factory, failure was due to materials or workmanship, repair or replacement will be made without charge. All pH and ORP sensors have a six (6) month limited warranty. If any sensor fails during that time, return the failed sensor to the factory, prepaid.
IX. GLOSSARY 442™ An Internationally recognized “natural water” standard developed by the Myron L Company in 1964. Algorithm A procedure for solving a mathematical problem. See Addendum, Temperature Compensation and TDS Derivation. Anions Negatively charged ions DVM Digital Volt Meter Hysteresis Dead Band — related to alarm setpoint. The amount of delay or overlap between change from high to low or low to high. LCD Liquid Crystal Display Logarithm An arithmetic function.
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XI. ADDENDUM A. pH, ORP and TEMPERATURE RELATIONSHIPS 1. pH a. pH as an Indicator pH is the measurement of Acidity or Alkalinity of an aqueous solution. It is also stated as the Hydrogen Ion activity of a solution. pH measures the effective, not the total, acidity of a solution. A 4% solution of acetic acid (pH 4, vinegar) can be quite palatable, but a 4% solution of sulfuric acid (pH 0) is a violent poison.
e. Sources of Error Because sources of error are much the same as for pH. Though the platinum surface will not break like the glass pH surface, its protective glass sleeve can be broken. A surface film will slow the response time and diminish sensitivity. It can be cleaned off with IPA, detergent, or acid, as with the pH glass. 3. pH and ORP SENSOR CAUTIONS Leaving high pH (alkaline) solutions in contact with the pH and /or sensor for long periods of time can damage it.
Myron L COMPANY 2450 Impala Drive Carlsbad, CA 92010-7226 USA Tel: +1-760-438-2021 Fax: +1-760-931-9189 E-Mail: info@myronl.com techquestions@myronl.com www.myronl.
