INSTRUCTION MANUAL Detcon Model PI-700 0-500ppb PI-700 VOC Gas Sensor This manual covers 0-500ppb range of PID based VOC Sensors DETCON, Inc. 4055 Technology Forest, Suite 100 The Woodlands, Texas 77387 Ph.281.367.4100 / Fax 281.298.2868 www.detcon.com Feb 10, 2011 • Document #3806 • Revision 0.
Model PI-700 0-500ppb This page left intentionally blank Model PI-700 0-500ppb ii
Model PI-700 0-500ppb Table of Contents 1. 2. 3. 4. 5. 6. 7. 8. 9. Introduction ..................................................................................................................................................1 1.1 Description.......................................................................................................................................... 1 1.2 Sensor Electronics Design ............................................................................................
Model PI-700 0-500ppb Table of Figures Figure 1 Typical Sensor Cell................................................................................................................................ 1 Figure 2 ITM Circuit Functional Block Diagram................................................................................................. 2 Figure 3 Sensor Assembly Front View ................................................................................................................
Model PI-700 0-500ppb 1. Introduction 1.1 Description Detcon Model PI-700 VOC gas sensors are non-intrusive “Smart” sensors designed to detect and monitor a wide range of VOC and Toxic gasses in air. Ranges of detection for target gasses are from 0-1ppm up to 0-5,000ppm. This model is specifically designed for use at 0-500ppb. The sensor features an LED display of current reading, fault and calibration status. The Sensor is equipped with standard analog 4-20mA and Modbus™ RS-485 outputs.
Model PI-700 0-500ppb program switches located on either side of the LED Display are activated via a hand-held magnetic programming tool, thus allowing non-intrusive operator interface with the ITM. Calibration can be accomplished without declassifying the area. Electrical classifications are Class I, Division 1, Groups B C D and are ATEX Approved for Class I, Zone 1, Group IIC area classifications..
Model PI-700 0-500ppb SS Splash Guard Adapter Lens and LED Display Replaceable Intelligent Plug-in Sensor Interconnect Wires PGM1 ZERO detcon inc. MODEL PI-700 VOC Sample Chamber PGM2 SPAN Magnetic Programming Switches O-Ring Housing Bottom Locking Set-Screw Intelligent Transmitter Module (ITM) Micro-processor controlled circuitry enclosed in an explosion-proof housing Figure 4 Sensor Assembly Breakaway 1.
Model PI-700 0-500ppb 2. Installation 2.1 ATEX Operational Guidelines for Safe Use 1. Install sensor only in areas with classifications matching with those described on the approval label. Follow all warnings listed on the label. Figure 6 PI-700 ATEX Approval Label 2. Ensure that the sensor is properly threaded into a suitable explosion-proof rated junction box with a downward pointing female ¾” NPT threaded connection.
Model PI-700 0-500ppb (1) Density of the gas to be detected (2) Most probable leak sources within the industrial process (3) Ventilation or prevailing wind conditions (4) Personnel exposure (5) Maintenance access (6) Additional placement considerations Density Placement of sensors relative to the density of the target gas is such that sensors for the detection of heavier than air gasses should be located within 4 feet of grade as these heavy gasses will tend to settle in low lying areas.
Model PI-700 0-500ppb 2.3 Sensor Contaminants and Interference PID VOC and toxic gas sensors will respond to any gas with an ionization potential <10.6eV. This is not a selective measurement technique, and hence can be used to measure a wide range of gases. Some of the most commonly present gasses that potentially cause PID interference are listed in Table 2 Gas Factor Table (refer to Section 9).
Model PI-700 0-500ppb 2.5 Electrical Installation The Sensor Assembly should be installed in accordance with local electrical codes. The sensor assemblies are designed for Class I, Division 1, Groups B, C, & D area classifications, and for ATEX Class I, Zone 1, Group IIC area classifications. Proper electrical installation of the gas sensor is critical for conformance to Electrical Codes. Refer to Figure 8 for proper electrical installation. 2.
Model PI-700 0-500ppb Green mA Black (-) Red (+) White B(-) Blue A(+) Wiring to Sensor Assembly Install a 100-250 Ohm resistor if the 4-20mA output is not used Customer Supplied Wiring (In) B(-) A(+) Wiring to Pump mA (-) (+) (-) Black (+) Red Mini Condulet RS-485 connections, Power, and 4-20mA to Control Device Figure 8 Sensor Wire Connections a) Remove the junction box cover. Identify the terminal blocks for customer wire connections.
Model PI-700 0-500ppb NOTE: The 4-20mA signal is held constant at 4mA for the first two minutes after power up. Initial Operational Tests After a warm up period of 1 hour (or when zero has stabilized), the sensor should be checked to verify sensitivity to the specific target gas of the application (not just Isobutylene span gas). Material Requirements -Detcon Span Gas (See Detcon for Ordering Information). Recommended span gas is 50% of range with Isobutylene in air or N2 balance (250ppb Isobutylene).
Model PI-700 0-500ppb 3. Operation 3.1 Programming Magnet Operating Instructions The Operator Interface of the Model 700 Series gas sensors is accomplished via two internal magnetic switches located to either side of the LED display (see Figure 10). The two switches, labeled “PGM1” and “PGM2”, allow for complete calibration and configuration, thereby eliminating the need for area declassification or the use of hot permits.
Model PI-700 0-500ppb 3.2 Operator Interface The operating interface is menu-driven via the two magnetic program switches located under the target marks of the sensor housing. The two switches are referred to as “PGM1” and “PGM2”. The menu list consists of three major items that include sub-menus as indicated below. (Refer to the complete Software Flow Chart.
Model PI-700 0-500ppb Software Flowchart Normal Operation PGM1 (3) PGM2 (10) PGM1 (3) PGM2 (3) AutoZero AutoSpan View Sensor Status Auto Time-Out PGM1/2 (M) PGM1/2 (3) Set AutoSpan Level Set Range Set Serial ID Auto Time-Out PGM1/2 (M) PGM1/2 (3) AutoTime-out PGM1/2 (M) PGM1/2 (3) Auto Time-Out PGM1/2 (M) PGM1/2 (3) Model Type Version X.
Model PI-700 0-500ppb 3.4 Calibration Mode 3.4.1 AutoZero The AutoZero function is used to zero the sensor. Local ambient air can be used to zero calibrate a VOC gas sensor as long as it can be confirmed that it contains 0ppb VOC’s. If this cannot be confirmed then a zero air (zero ppm VOC) cylinder should be used. Optionally, a Carbon Scrubber can be used to provide a VOC-free gas sample for zero calibration.
Model PI-700 0-500ppb NOTE 1: Contact Detcon for Ordering Information on Span Gas cylinders. NOTE 2: For span, an Isobutylene gas concentration of 50% of range is strongly recommended. This should be supplied at a controlled flow rate of 500cc/min using the in-line humidifying tube. Other concentrations can be used if they fall within allowable levels of 5% to 100% of range. NOTE 3: If Isobutylene is used as span gas, the correct Gas Factor must be used.
Model PI-700 0-500ppb b) Verify that the AutoSpan Level is equal to the Calibration Span Gas Concentration. (Refer to View Sensor Status in Section 3.5.1.) If the AutoSpan Level is not equal to the Calibration span gas concentration, adjust the AutoSpan Level as instructed in Section 3.5.2 Set AutoSpan Level. c) From Normal Operation, enter Calibration Mode by holding the programming magnet over PGM1 for 3 seconds.
Model PI-700 0-500ppb be set on the Modbus™ output. NOTE 3: If the sensor fails the stability criteria, a “Stability Fault” will be declared and a “Fault Detected” message will be displayed alternately with the sensor’s current reading. The 4-20mA output will be taken to 0mA and the ‘Stability Fault’ fault bit will be set on the Modbus™ output.
Model PI-700 0-500ppb remaining sensor life, gas factor, zero offset, mA output, input voltage, sensor ambient temperature, gain setting, and the sensor’s raw counts. From the View Sensor Status text scroll, hold the magnet over PGM1 or PGM2 until the “V” prompt appears and continue to hold the magnet in place for an additional 3-4 seconds (until the display starts to scroll “Status Is”).
Model PI-700 0-500ppb Gain Setting The menu item appears as: “Gain XX” Raw Counts The menu item appears as: “Counts XXXX” When the status list sequence is complete, the ITM will revert to the “View Sensor Status” text scroll.
Model PI-700 0-500ppb 3.5.4 Set Range The full-scale range of a PI-700 sensor is determined at the time of order. The Intelligent Plug-in Sensor is factory calibrated for this range. However, if the application requirements change and the user needs to alter the original range, the “Set Range” function can be used to make field adjustments. The currently selected full-scale range is displayed in the “View Sensor Status” menu.
Model PI-700 0-500ppb displayed. Hold the magnet over PGM1 or PGM2 for 3 seconds to accept the new value. The display will scroll “Factor Saved”, and revert to “Set Gas Factor” text scroll. Move to another menu item by executing a momentary hold, or, return to Normal Operation via automatic timeout of about 15 seconds (the display will scroll “Set Gas Factor” 4 times and then return to Normal Operation. 3.5.
Model PI-700 0-500ppb Move to another menu item by executing a momentary hold, or, return to Normal Operation via automatic timeout of about 15 seconds. 3.5.8 Restore Factory Defaults Restore Factory Defaults is used to clear current user configuration and calibration data from memory and revert to factory default values. This may be required if the settings have been configured improperly and a known reference point needs to be re-established to correct the problem.
Model PI-700 0-500ppb measurement mode. This feature also allows the user to log the AutoZero and AutoSpan events via their master control system. Sensor Life Sensor Life is calculated after each AutoSpan calibration and is reported as an indicator of remaining service life. It is reported in the “View Sensor Status” menu and as a RS-485 Modbus™ register bit. Sensor Life is reported on a scale of 0-100%.
Model PI-700 0-500ppb will not clear until the fault condition has been cleared. The sensor should be considered as ‘Out-of-Service’ until a successful AutoSpan calibration is performed. Zero Fault If the sensor drifts to < -10% of range, an “Under-Range Fault” will be declared. An “Under-Range Fault” will cause a “Fault Detected” message to flash intermittently on the ITM display.
Model PI-700 0-500ppb AutoSpan Fault If 180 days has elapsed since the last successful AutoSpan, an AutoSpan Fault will be generated. An “AutoSpan Fault” will cause the “Fault Detected” message to flash intermittently on the ITM display. The Modbus™ fault register bit for AutoSpan Fault will be set and will not clear until the fault condition has been cleared by executing a successful AutoSpan. If an AutoSpan occurs, the 4-20mA signal remains operational. PI-700 0-500ppb Instruction Manual Rev. 0.
Model PI-700 0-500ppb 4. RS-485 Modbus™ Protocol Model PI-700 sensors feature Modbus™ compatible communications protocol and are addressable via the program mode. Other protocols are available. Contact the Detcon factory for specific protocol requirements. Communication is two wire, half duplex 485, 9600 baud, 8 data bits, 1 stop bit, no parity, with the sensor set up as a slave device. A master controller up to 4000 feet away can theoretically poll up to 256 different sensors.
Model PI-700 0-500ppb Bits read as 0 are FALSE, bits read as 1 are TRUE Status Bits High Byte: Bit 15 – Reserved Bit 14 – Calibration Mode Bit 13 – Reserved Bit 12 – Sensor Fault 2 Bit 11 – Zero Fault Bit 10 – Sensor Fault Bit 9 – Range Fault Bit 8 – Stability Fault Status Bits Low Byte: Bit 7 – Clearing Fault Bit 6 – Processor Fault Bit 5 – Memory Fault Bit 4 – Input Voltage Fault Bit 3 – 4-20mA Fault Bit 2 – Temperature Fault Bit 1 – Auto Span Fault Bit 0 – Global Fault PI-700 0-500ppb Instruction Manua
Model PI-700 0-500ppb 5. Service and Maintenance Calibration Frequency In most applications, quarterly span calibration intervals will assure reliable detection. However, industrial environments differ. Upon initial installation and commissioning, close frequency tests should be performed, weekly to monthly. Test results should be recorded and reviewed to determine a suitable calibration interval. If, after 180 days, an AutoSpan Calibration is not performed, the ITM will generate an AutoSpan Fault. 5.
Model PI-700 0-500ppb General recommendations for Sensor Maintenance For normal environmental exposure and signal decay, replace the plug-in sensor every 9-12 months. (especially if there are no skilled technicians to handle proper UV lamp replacement.) If skilled technicians are available, replace just the UV lamp every 9-12 months. For abnormally high rates of signal decay, clean the UV lamp monthly, using a Lamp Cleaning Kit, and replace the UV lamp every 9-12 months.
Model PI-700 0-500ppb Figure 15 Removal of Filter Cap 3. With a fine tipped tweezers, remove both the Filter Media and set aside. Figure 16 Removal of Filter Media 4. Using the Exacto Blade, remove the spacer and set it aside. Figure 17 Removal of Spacer 5. With fine tipped tweezers, carefully remove the cell assembly by prying under the cell’s edge where the connector pins are located. PI-700 0-500ppb Instruction Manual Rev. 0.
Model PI-700 0-500ppb Figure 18 Removal of Cell Assembly 6. With fine tipped tweezers, grasp the lamp by placing the tips in the housing notch and gently pulling it out. Be careful not to scratch the lamp lens or chip the edges. Figure 19 Removal of Lamp Cleaning the Lamp Figure 20 Lamp cleaning Wearing gloves, grab the lamp by the cylindrical glass body and clean the window by rubbing it against the Polishing Pad. Use a circular motion and try to keep the window surface flat relative to the pad.
Model PI-700 0-500ppb of rubbing should be enough in most cases. Another indication of cleaning completeness is that about 1/16th of the pad surface is used during the process. Figure 21 Polishing the Lamp Reassembly 1. Install the lamp into the sensor, making sure that the lamp’s metalized pads are aligned with the corresponding excitation springs inside the lamp cavity Figure 22 Lamp installation 2.
Model PI-700 0-500ppb 3. Using fine tipped tweezers, install the cell assembly. Align the pins with the corresponding sockets on the sensor and push down on the end with the pins. Make sure the cell assembly is flush with the lamp window. Figure 24 Cell Assembly installation 4. Place the spacer around the assembly. Figure 25 Spacer installation 5. Place the filter media over the Cell Assembly centered on the top of the sensor. Make sure the filters are installed in the correct order.
Model PI-700 0-500ppb 6. Align the Cap Key with the notch on the housing. Starting at the side opposite the notch, press down until the Filter Cap snaps on to the housing. If the Cap Key is incorrectly aligned there will be a noticeable bulge on the side of the cap. Figure 27 Replacing the Cap Visual Inspection The Sensor should be inspected annually. Inspect for signs of corrosion, pitting, and water damage.
Model PI-700 0-500ppb d) Gently pull the plug-in sensor out of the ITM. Transfer to new plug-in sensor. Orient the new plug-in sensor so that it matches with the female connector pins. When properly aligned, press the sensor in firmly to make the proper connection.
Model PI-700 0-500ppb Replacement of PI-700 Sensor Assembly. a) Remove the power source from the sensor assembly. Disconnect all sensor wire connections at the J-Box. NOTE: It is necessary to remove power to the J-Box while changing the PI-700 sensor in order to maintain area classification. b) Use a wrench and the wrench flats provided at the top section of the ITM and unthread the ITM until it can be removed.
Model PI-700 0-500ppb 6. Troubleshooting Guide Refer to the list of Failsafe Diagnostic features listed in Section 3.6.2 for additional reference in troubleshooting activities. Listed below are some typical trouble conditions and their probable cause and resolution path. Locking Setscrew Display Window ITM Bottom View Plug-in Sensor (Bottom View) Figure 30 Sensor Cell and ITM Mating Under-Range Fault Probable Cause: Sensor Baseline drifted lower, Ambient Interference gasses reduced. Repeat AutoZero.
Model PI-700 0-500ppb Check validity of span gas using pull tube or other means (check MFG date on cal gas cylinder). Use proper cal gas regulators and tubing for highly corrosive gasses. Check for obstructions affecting cal gas hitting sensor face (including being wet, blocked, or corroded). Verify adequate Sensor Life. Clean or replace the PID lamp. Replace the plug-in VOC sensor.
Model PI-700 0-500ppb Unreadable Display If due to excessive sunlight, install a sunshade to reduce glare. Nothing Displayed – Transmitter not Responding Verify condulet has no accumulated water or abnormal corrosion. Verify required DC power is applied to correct terminals. Swap with a known-good ITM to determine if ITM is faulty. Faulty 4-20 mA Output If Sensor has a normal reading with no Faults displayed, and the 4-20 mA signal output is 0mA….
Model PI-700 0-500ppb 7. Customer Support and Service Policy Detcon Headquarters Shipping Address: 3200 A-1 Research Forest Dr., The Woodlands Texas 77381 Mailing Address: P.O. Box 8067, The Woodlands Texas 77387-8067 Phone: 888.367.4286, or 281.367.4100 Fax: 281.292.2860 • www.detcon.com • service@detcon.com • sales@detcon.com All Technical Service and Repair activities should be handled by the Detcon Service Department via phone, fax, or email at contact information given above.
Model PI-700 0-500ppb 8. PI-700 Sensor Warranty Intelligent Plug-in Sensor Warranty Detcon Inc. warrants, under normal intended use, each new intelligent plug-in sensor for a period of twelve months and under the conditions described as follows: The warranty period begins on the date of shipment to the original purchaser. The sensor element is warranted to be free of defects in material and workmanship.
Model PI-700 0-500ppb 9. Appendix 9.
Model PI-700 0-500ppb Status Indicators: 4-digit LED Display with gas concentration, full-script menu prompts for AutoSpan, Set-up Options, and Fault Reporting Faults Monitored: Loop Fault, Input Voltage Fault, Missing Sensor Fault, Zero Fault, Processor Fault, Memory Fault, Calibration Fault(s) Cable Requirements: Power/Analog: 3-wire shielded cable Maximum distance is 13,300 feet with 14 AWG Serial Output: 2-wire twisted-pair shielded cable specified for RS-485 use Maximum distance is 4,000 feet to
Model PI-700 0-500ppb Table 2 Gas Factor Table Compound Name Acetaldehyde Acetic Acid Acetic Anhydride Acetone Acetonitrile Acetylene Acrolein Acrylic Acid Acrylonitrile Allyl alcohol Allyl chloride Ammonia Amyl alcohol Aniline Anisole Arsine Benzaldehyde Benzene Benzonitrile Benzyl alcohol Benzyl chloride Benzyl formate Boron trifluoride Bromine Bromobenzene 2-Bromoethyl methyl ether Bromoform Bromopropane, 1Butadiene Butadiene diepoxide, 1, 3Butane Butanol, 1Butanol, tButene, 1Butoxyethanol, 2- Synonym/
Model PI-700 0-500ppb 1 Compound Name Synonym/Abbreviation Formula Response Factor Carbon tetrachloride Carbonyl sulfide Cellosolve (see 2-Ethoxyethanol) CFC-14 (see Tetrafluoromethane) CFC-113 (see 1,1,2-Trichloro-1,2,2trifluoroethane) Chlorine Chlorine dioxide Chloro-1,3-butadiene, 2Chlorobenzene Chloro-1, 1-difluoroethane, 1-(R-142B) Chlorodifluoromethane Chloroethane Chloroethanol Chloroethyl ether, 2Chloroethyl methyl ether,2Chloroform Chloropicrin Chlorotoluene, oChlorotoluene, pCrotonaldehyde Cu
Model PI-700 0-500ppb 1 Compound Name Synonym/Abbreviation Formula Response Factor Dichloro-1,1,1-trifluoroethane, 2,2- R123 C2HCl2F3 NR + 11.5 ne C4H7Cl2O4P 0.9 + <9.4 0.1 C10H12 m.w. 226 m.w. 216 C4H11N C7H18N2 C8H12O4 0.5 0.9 0.7 1 1.3 4 + + + + 8.8 5 8.01 5 C6H15N C4H4O2 C4H9NO C2H7N C3H6O3 C2H6S2 C4H11N C3H7NO C2H8N2 0.74 2.0 0.8 1.5 ~70 0.20 1.0 0.8 0.
Model PI-700 0-500ppb Compound Name Synonym/Abbreviation Gasoline #2, 92 octane 1,5-Pentanedial, Glutaric dialdehyde 2-Bromo-2-chloro-1,1,1trifluoroethane Glutaraldehyde Halothane HCFC-22 (see Chlorodifluoromethane) HCFC-123 (see 2,2-Dichloro1,1,1-trifluoroethane, R-123) HCFC-141B (see 1,1Dichloro-1-fluorethane) HCFC-142B (see 1-Chloro1,1-difluoroethane) HCFC-134A (see 1,1,1,2Tetrafluoroethane) HCFC-225 (see Dichloropentafluoropropane) Heptane, nHexamethyldisilazane,1,1,1,3 ,3,3Hexane, n Hexanol, 1Hexen
Model PI-700 0-500ppb Compound Name Kerosene (C10-C16 petro. distillate - see Jet Fuels) MDI (see 4,4'-Methylenebis (phenylisocynate)) Mesitylene Methane Methanol Methoxyethanol, 2Methoxyethoxyethanol, 2- Synonym/Abbreviation Formula Response Factor 1,3,5-Trimethylbenzene Natural gas Methyl alcohol, carbinol Methyl cellosolve, Ethylene glycol monomethy ether 2-(2-Methoxyethoxy)ethanol Diethylene glycol monomethyl ether C9H12 CH4 CH4O 0.35 NR NR + + + 8.41 12.51 10.85 ne ne 200 C3H8O2 2.4 + 10.
Model PI-700 0-500ppb Compound Name Synonym/Abbreviation Nonane Octane, nPentane Peracetic acid Peracetic/Acetic acid mix Perchloroethene PGME PGMEA Phenol Phosgene Phosphine in N2 Photocopier Toner Picoline, 3Pinene, aPinene, b Piperylene, isomer mix Propane Propanol, nPropene Propionaldehyde Propyl acetate, nPropylene carbonate Propylene glycol Propylene oxide Propyleneimine Peroxyacetic acid, Acetyl Hydroperoxide Peroxyacetic acid, Acetyl Hydroperoxide PCE, Perchloroethylene, Tetrachloroethylene Prop
Model PI-700 0-500ppb Compound Name Synonym/Abbreviation Formula Tetramethyl orthosilicate Methyl silicate, TMOS Dowthern,3:1 Diphenyl oxide: Biphenyl Methylbenzene TDI, 4-Methyl-1,3-phenylene2,4- diisocyanate 1,2,4-TCB 1,1,1-TCA, Methyl chloroform 1,1,2-TCA TCE, Trichloroethylene C4H12O4Si C12H10O C12H10 C7H8 Therminol VP-1 Toluene Tolylene-2,4-diisocyanate Trichlorobenzene, 1,2,4Trichloroethane, 1,1,1Trichloroethane, 1,1,2Trichloroethene Trichlorotrifluoroethane, 1,1,2- CFC-113 Triethylamine TEA T
Model PI-700 0-500ppb Part Number 927-P25500-0X5 600-003809-000 377-P10000-0X5 500-003087-100 351-152021-200 Spare Parts PI-700 Intelligent Transmitter Module (ITM for VOC Gas Sensors) Model PI-700 SS Splash Guard Adapter Replacement Plug-in VOC gas sensor (0-500ppb) Transient Protection PCA 24VDC Pump Assembly Sensor Accessories 327-000000-000 Programming Magnet Calibration Accessories 943-100000-VOC 942-001123-000 See Detcon 943-090005-52P Span Gas Kit: Includes 1000cc/min fixed flow regulator, Tefl
Model PI-700 0-500ppb 9.4 Revision History Revision 0.0 Date 01/27/12 PI-700 0-500ppb Instruction Manual Changes made Initial Manual release. Approval BM Rev. 0.
Model PI-700 0-500ppb 9.5 Model PI-700 Engineering Drawings 1) PI-700 0-500ppB Dimensional and Overview 2) PI-700 0-500ppb Wiring PI-700 0-500ppb Instruction Manual Rev. 0.
Model PI-700 0-500ppb This page left intentionally blank Shipping Address: 4500 Technology Forest, Suite 100, The Woodlands Texas 77381 Mailing Address: P.O. Box 8067, The Woodlands Texas 77387-8067 Phone: 888.367.4286, 281.367.4100 • Fax: 281.292.2860 • www.detcon.com • sales@detcon.com PI-700 0-500ppb Instruction Manual Rev. 0.
