Honeywell Lr953291 Manual
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1 EN1C-0015SZ20 R0314 PRODUCT HANDBOOK C7061 A/F DYNAMIC SELF CHECK ULTRAVIOLET FLAME DETECTOR APPLICATION The C7061A is a dynamic self-checking flame detector for sensing the ultraviolet radiation generated by the combus- tion of gas, oil, or other fuels. This flame detector is available in two versions: model C7061A for use in Standard applications, and model C7061F for use in installations requiring explosion-proof packaging. The flame detector is designed for use with either, R7061 Dynamic Self-Check Ultraviolet amplifier and • R4348 Flame Switch or, or with, R7861A Dynamic Self-Check Ultraviolet amplifier and, • 7800 SERIES Burner Programmers These configurations provide a closed-loop, self-checking circuit which insures the integrity of both amplifier and flame detector. Improper response simulated flame loss results in a safety shutdown and/or alarm. model C7061F CONTENTS GENERAL Description ..................................................................... 2 Features ......................................................................... 2 Orderdering information ................................................. 2 TECHNICAL DATA Specification................................................................... 3 Standards and approvals...............................................4 Replacement parts and accessories ..............................4 Dimensional drawing ...................................................... 5 INSTALLATION AND OPERATION Planning the installation................................................. 6 Installation ...................................................................... 8 Wiring ........................................................................... 10 Adjustement and checkout ........................................... 12 VARIOUS Troubleshooting............................................................ 13 Service.........................................................................14 ATEX certificate INERIS 03ATEX0158X......................16 model C7061A
EN1C-0015SZ20 R0314 2 GENERAL DESCRIPTION The C7061Axxxx and C7061F1xxx detector models are identical except for housings. Model C7061F detector is for use in installations requiring explosion proof packaging. The housing is conform the EExd IIC T6 classification. More details for the explosion proof housing can be found in the chapter Standards and Approvals. The C7061F model has a 1-inch NPT tapping for mounting onto a sight pipe. For allowable mounting positions of model C7061A and model C7061F, see Page 9. The terminal block on both models is of wire clamp type with removable screws and is situated in the compartment of the C7061. The UV cell contains an ultraviolet sensing tube, shutter assembly, terminal block and magnifying lens. The UV sensor can be mounted from the programmer/flame switch up to a length of 300 m. FEATURES • Oscillating shutter interrupts ultraviolet radiation reach- ing the UV Sensor 12 times per minute (when used with R7861 amplifier in combination with 7800 SERIES) to provide the UV Sensor tube checking function. When used with the R7061 amplifier in combination with R4348 flame switch, the shutter frequency is 60 times per minute. Amplifier circuitry components are checked from the microprocessor in the 7800 SERIES Control. • Detectors can be mounted horizontally, vertically or at any angle in between. The self-checking C7061 models require faceplate alignment and have integral locating reference points to assure proper operation of the shut- ter mechanism. • Ultraviolet radiation sensing tube and quartz viewing window are field replaceable. • Two flame detectors can be wired in parallel to reduce nuisance shutdowns in difficult flame sighting applica- tions. • A swivel mount is available to facilitate flame sighting. • -40°C (-40°F) rated ultraviolet sensing tube is available. • lncorporates UV Sensor tube checking feature; used with R7061 and R7861 Dynamic Self-Check amplifiers. • High pressure 50 psi (345 kPa) quartz viewing window, magnifying lens and antivibration mount are available as accessories. • Housing meets IP67 enclosure standards. • C7061 F only: explosion-proof housing, meets EExd IIC T6 classification. • Protective heat block built into mounting flange. ORDERING INFORMATION When ordering specify: • Complete model number. Order separately: • R7061 Dynamic Self-Check Ultraviolet Amplifier. • R7861A Dynamic Self-Check Ultraviolet Amplifier. • Replacement parts, if desired. • Accessories, if desired • Flame safeguard control
3 EN1C-0015SZ20 R0314 TECHNICAL DATA SPECIFICATION Models C7061A: Self checking UV flame detector in standard housing. C7061F: Self checking UV flame detector in explosion proof housing. Designed for use with either, R7061 Dynamic Self-Check Ultraviolet amplifier and • R4348 Flame Switch or with, R7861A Dynamic Self-Check Ultraviolet amplifier and, • 7800 SERIES Burner Programmers Ambient Operating temperature ratings C7061A -40°C to +70°C (-40°F to +160°F) (derate ambient 1°F for every 13°F of aspirator temperature over 160°F). C7061F: -20°C to +70°C (-22°F to +160°F) Storage temperature ratings • -51°C to +85°C (-60°F to +185°F) Voltage and Frequency C7061A1004 120 VAC, 50/60 Hz C7061A1020 / C7061A1079 115/230 VAC, 50/60 Hz C7061F1003 115/230 VAC, 50/60 Hz The System operates correctly at a nominal voltage (-15%, +10%), 50/60 Hz. Flame Signal Measured at the flame current meter jac k. C7061 Detector: 1.4 to 5.5 micro amps (nominal). R7061A Amplifier: 2.5 to 5.5 micro amps (nominal). R7861A Amplifier: 1.25 to 5.0 Volts (On keyboard display module). Flame Signal amplifier R7061A Dynamic Self-Check Ultraviolet amplifier R7861A Dynamic Self-Check Ultraviolet amplifier (Order separately) lnterchangeability Models C7061A and C7061F are not interchangeable with other flame detector models. Shutter frequency 0.2 Hz, nominal (when used in combination with 7800 SERIE). Interrupts the line-of-sight of the detector about 12 times per minute to provide self-checking. Any malfunction in the flame detection system results in a safety shutdown. 1 Hz nominal when used with R4348 in combination with R7061 amplifier. Pressure rating of quarz viewing window C7061A: 138 kPa (20 psi) maximum. C7061F: 690 kPa (100 psi) maximum Dimensions C7061A: see figure 1. C7061F: see figure 2. Housing C7061A: Construction: cast-aluminum cover. Color: Violet. Mounting flange (with heat block) and faceplate are sepa- rate to provide heat insulation and seal-Off. C7061F: Meets requirements (explosion-proof): EEx d IIC T6 Construction: cast-aluminum Cover, Ineris AD4320001 . Color: Violet. Mounting flange (with heat block) and face- plate are separate to provide heat insulation and seal-Off. Enclosure C7061A: Meets IP66 enclosure requirements (indoor, outdoor protection; rain-tight, dust-tight, hose-directed water). Optional water jacket available. C7061F: IP65 according to DIN 40050 Weight C7061A: 3.3 kg (7.3 Ib) C7061F: 6.3 kg (13.9 Ib) Mounting and orientation C7061A : Mounting flange with 3/4 inch NPT internal threads for attaching to sight pipe. C7061F: Mounting flange with 1 inch NPT internal threads for attaching to sight pipe. For allowable mounting positions of model C7061A and F, see Page 9. Wiring Connections C7061A1004: NEC Class 1 color coded leadwire. Length: 8 ft (2.4m). C7061A1020 and C7061A1079: Terminal block Threaded leadwire opening in faceplate: 1/2-14 NPSM internal threads for attaching conduit. One brass cable gland standard with housing. For C7061F only: Terminal block: Terminal block inside the housing, wire clamp type, remov- able screws (terminal lugs can be used). Cable entry holes: One brass cab le gland Ex classification: EExdII C, is standard provided in the housing. Inner sheath diameter 6 to 12 mm Outer sheat diameter 8.5 to 16 mm Tightening torque: • cable gland into rear cover plate: 20 Nm • cap into cable gland: 3 Nm Serviceability Field replaceable viewing window and ultraviolet sensing tube, coil and shutter assembly. Maximum cable length 30-50m between sensor and amplifier, depending on local conditions (presence of noise, parallel cables, etc) Design life Ultraviolet sensing tube: limited life, see sections Trouble- shooting and Service.
EN1C-0015SZ20 R0314 4 STANDARDS AND APPROVALS Models C7061A and F C7061A and F Ultraviolet Flame Detector conform with following EC-Directives: • Gas Appliance Directive (90/396/EEC). according to European Standard: EN298 approved with R7861 and R7061 flame ampli- fiers. • Low Voltage Directive (73/23/EEC) according to European Standard: EN60730-2-5 • Electro Magnetic Compatibility Directive (89/336/EEC) according European Standards: EN55011 class B regarding emission. EN50082-2 industrial level regarding immunity. Model C7061F In addition to above information, C7061F conforms with: • Explosive Atmospheres Directive (94/9/EC) according to European Standards: EN50014 EN50018 EN50019• ATEX (INERIS 03ATEX0158X) housing model AD4320001/2 Other approvals (C7061A only) Underwriters Laboratories Inc. Listed. Canadian Standards Association Cer tified: Master File LR95329-1. Factory Mutual Approved: 14740.01. lndustrial Risk Insurers Acceptable. REPLACEMENT PARTS AND ACCESORIES Replacement parts for model C7061A and C7061F 129464M Uttraviolet Sensing Tube. 129464N Ultraviolet Sensing Tube; for -40°F (-40°C) opera- tion (standard). 190971B Coil and Shutter Assembly. Replacement parts for model C7061A 114372 Quartz Viewing Window; rated for 20 Psi (138 kPa). 114465 Gasket, Silicone rubber; for installing viewing window (three required). 120739 Gasket, fiber-neoprene; heat insulation and seal- off for mounting flange. Accessories for model C7061A and C7061F 118367A Swivel mount. 118369 Bushing, galvanized iron, with 3/4 inch NPT inter- nal threads on one end and 1 inch NPT external threads on the other end. For adapting a detector with 1 inch NPT internal threads (for mounting) to a 3/4 inch sight pipe, or to the pipe nipple and tee for connecting an air supply. 120934 Mounting Flange, aluminum, with 3/4 inch NPT internal threads for attaching to sight pipe. 124198 Mounting Flange, aluminum, with 1 inch NPT internal threads for attaching to sight pipe. 123539 Antivibrtation Mount. 124204 Quartz Focusing Lens, rated for 20 Psi (138 kPa); for increasing the detector-sensed ultravio- let radiation. Included in C7061A1079 and C7061F1xxx. Accessories for model C7061A 122748 Quartz Viewing Window, rated for 50 Psi (345 kPa). 190105 Water Jacket.
5 EN1C-0015SZ20 R0314 DIMENSIONAL DRAWING Fig. 1. Dimensional drawing C7061A in inches (mm) Fig. 2. Dimensional drawing C7061F1xxx in mm
EN1C-0015SZ20 R0314 6 INSTALLATION AND OPERATION PLANNING THE INSTALLATION Proper flame detector application is the back of a safe and reliable flame safeguard installation. Refer to the burner manufacturer’s instructions as well to those included here. Follow all instructions carefully. CAUTION 1. Do not connect these detectors to non-Hon- eywell manufactured controls (primaries, pro- grammers, multiburner systems, and burner management systems). Unsafe conditions could result. 2. Disconnect power supply before beginning installation to prevent electrical chock and equipment damage. More than one discon- nect may be involved. 3. All wiring must be NEC Class 1 (line volt- age). 4. Voltage and frequency of the power supply- connected to this detector must agree with the values marked on the detector. 5. Sight the detector so it does not respond to ignition spark. 6. On multiburner installations, each detector must respond only to the flame of the burner it is supervising. IMPORTANT Do not connect more than two C7061A/F flame detectors in parallel. Basic Requirements The combustion flames of most carbon-based fuels emit sufficient ultraviolet radiation to enable the C7061A/F Solid State (Purple Peeper) ultraviolet flame detector to prove the presence of a flame in a combustion chamber. The detec- tor mounted outside the combustion chamber. Its mounting flange or union is threaded to one end of a sight pipe inserted through the wall of the combustion chamber. The ultraviolet sensing tube in the flame detector sights the flame through the pipe. When a flame is present, the UV tube in the C7061A/F senses the ultraviolet radiation emitted. The C7061A/F pro- duces a signal that is sent to the amplifier in the flame safe- guard control. The amplified signal pulls in the flame relay in the control to allow proper operation of the system. Because it is necessary for the UV sensing tube to actually see the flame, it is best to locate the detector as close to flame as physical arrangement, temperature, and other restrictions permit. These restrictions are described in detail in the following paragraphs. Determine the location Before beginning the actual installation, estimate the best location for mounting the detector based upon these factors: 1. Temperature Install the flame detector where the surrounding tempera- ture will remain within the specified ambient operating tem- perature ratings. For the C7061A/F, to keep the detector temperature within specifications. If the temperature rating is exceeded, the introduction of cooling air will be necessary. 2. Vibrations Do not install the detector where it could be subject of excessive vibration; it shortens the life of the electronic com- ponents. Vibrations with a magnitude greater than 1g will require an anti-vibration mount to cushion the detector. 3. Clearance Make sure there will be enough room to remove the cover of the detector for servicing. Radiation sour ces other than flame Examples of radiation sourses, other than flame, which could actuate the detection system: Ultraviolet sources • Radiant surfaces above 1200°C (2200°F). • Sparks from ignition transformers and welding arcs. • Gas lasers • Sun lamps • Halogen lamps • Germicidal lamps • lncandescent lamps held close to the sensing tube • Filament above 1200°C (2200°F). Gamma ray and X-ray sources • Diffraction analyzers • Electron microscopes • Radiographic X-ray machines • High voltage vacuum switches • High voltage condensers • Radioisotopes Except under very unusual circumstances, none of these sources, except a radiant surface or ignition spark, would be present in or near the combustion chamber. The detec- tor may respond to a radiant surface at a temperature above 1200°C (2200°F) if both of the following conditions are pres- ent the surface represents a significant percentage of detec- tor’ s field of vie w. If the temperature or a radiant surface causes the flame relay (in the flame safeguard control) to pull in, re-aim the sight pipe so the detector views a cooler area, or the sen- sitivity of the detector decreases. lgnition sparks is a rich source of ultraviolet radiation.
7 EN1C-0015SZ20 R0314 IMPORTANT When installing the detector, make sure it does not respond to ignition spark. Single burner requirements The detector must have an unobstructed view of the flame it is supervising under all firing conditions. This implies a proper sighting angle and the minimization of screening effects. Sighting angle The first 30 percent of a flame (the root) radiates the most intense ultraviolet energy. The low angle sighting permits the detector to view a greater depth of the flame root, thus reducing the effects of irregularities in the flame pattern. The best sighting angle is nearly parallel to the axis of the flame, as shown in Figure 3. NOTE: When possible, it is desirable to tilt the detector and sight pipe downwards to prefent the build up of soot in the pipe or on the viewing lens. In most installations, the detector will need to respond to the, pilot flame alone, then to the pilot and main burner flame together and finally to the main burner flame alone. The detector must meet all sighting requirements which apply: 1. Pilot flame alone - the smallest pilot flame that can be detected must be capable of reliable ignition the main burner. 2. Pilot and main burner flame together - the detector must sight the junction of both flames. 3. Main burner flame alone - the detector must sight the most stable part of the flame for all firing rates Screening effects Smoke, fuel mist, dirt and dust are masking agents that absorb ultraviolet radiation from the flame. They create a screen that reduces the amount of ultraviolet radiation reaching the detector and may cause flame signal deteriora- tion resulting in a shutdown. The adverse affects of Screen- ing may be minimized by proper burner adjustment, increas- ing the detector viewing area (shorten sight pipe and/or increase its diameter). Multifuel requirements In addition to meeting the requirements for a single burner, a multiburner installation also requires flame discrimina- tion. Flame discrimination may be defined as the location of all flame detectors such that each detector responds only to the flame(s) produced by the burner it is supervising. Multiburner requirements In multiple burner systems, not every detector can be posi- tioned so its line of sight does not intercept flames from other burners. This situation occurs in front-fired boiler furnaces having more than one row of burners, or in multi- level opposed-fired furnaces where the burners face each other. When planning such an installation, locate each flame detector so that it has the best possible view of the root of the flame(s) it is supervising and the worse possible view of all other flames. Figure 4. illustrates a critical detector application Problem requiring flame discrimination. Flame discrimination is accomplished by detector 1 by reducing its sensitivity until the flame relay (in the flame safeguard control) does not respond to flame 2. Note that detector 1 is aimed at the root of Flame 1 where UV (ultraviolet) energy is most inten- sive. Although it sights flame 2 is not aimed at the root of flame 2. The sensitivity of detector 1 is reduced to a point that ensures maximum sensitivity to flame 1 while rejecting flame 2. similarly, detector 2 is adjusted to ensure maximum sensitivity to flame 2 while rejecting flame 1. If the sensitivity control on a detector is set at its minimum position and flame discrimination cannot be achieved, insert an orifice plate in the sight pipe. An orifice of the proper diameter will reduce the ultraviolet radiation reaching the detector so that the sensitivity can be adjusted to effect flame discrimination. P arallel flame detector s Two C7061A/F detectors can be connected in parallel to the same flame signal amplifier and still provide independent sensitivity adjustment. This capability is particular useful for multiburner, multifuel applications. Shifting flame patterns, commonly encountered on burners with wide turndown ratios, may require parallel detectors to prove the flame at the highest and lowest firing rates. In this case, one detector supervises the pilot (interrupted) and both detectors supervise the main burner flame. During the main burner “run” period, either detector is capable of maintaining system operation. In addition to assuring more reliable flame detection, par- allel detectors facilitate maintenance during burner opera- tion. Each detector can be removed in turn without shutting down the supervised burner. However, a flame simulating failure occurring in the flame signal amplifier or in either detector will cause a shutdown.Fig. 3. Sighting angle Fig. 4. Critical detector application problem
EN1C-0015SZ20 R0314 8 INSTALLATION CAUTION 1. lnstaller must be a trained, experienced flame safeguard control serviceman. 2. Disconnect power supply before beginning installation to prevent electrical shock and equipment damage. 3. All wiring must comply with applicable local electrical codes, ordinances and regulations. 4. Voltage and frequency of power supply con- nected to this detector must agree with the values marked on the detector. 6. On multiburner installation, each detector must respond only to the flame(s) producted by the burner it is supervising. 7. Do not connect more than two detectors in parallel to a single R7061 or R7861A Dynamic Self-Check Ultraviolet amplifier. 8. Perform all required adjustments and check- out tests after installation is complete. lnstall the Sight Pipe After you have determined the location and sighting angle, select the sight pipe. A black iron pipe with a diameter of at least 1-1/2 in. (38.1 mm) is recommended. Do not use stain- less steel or galvanized pipe because they reflect ultraviolet radiation internally and complicate aiming the pipe. Sight pipes with diameters 2 to 3 in. (51 to 76 mm) produce better results for horizontal rotary burners, which require wide viewing angles. A wide viewing angle can also be obtained by using a short sight pipe. Prepare Hole in Wall of Combustion Chamber Cut or drill a hole of the proper diameter for the sight pipe in the wall of the combustion chamber at the selected loca- tion. Flare the hole to leave room for small adjustments of the sighting angle. The taper of the hole should be about 1 in. for every 3 in. (25 mm for every 76 mm) of Wall thickness. Mount Sight Pipe Thread one end of the pipe to fit the mounting flange, union,or required coupling. Cut the pipe to the desired length (as short as practical) and at an angle so it fits flush with the wall of the combustion chamber. Tack weld the pipe to the wall in a trial position. Do not weld the sight pipe perma- nently in place until after completing the Adjuctments and Checkout. lnstall Fittings In some cases, the sight pipe does not directly fit the C7061A/F mounting flange or union. Also, it may be desir- able or necessary to ventilate the sight pipe. You may also want to use a swivel mount or an antivibration mount. Each of these cases may require additional fittings. Reducer For sight pipes of larger diameter than the mounting flange connector or union, install a reducer as illustrated in Fig. 5. The reducer will require a close nipple with these external threads: 3/4 or 1 inch. NPT. Sight Pipe Ventilation It may be necessary to ventilate the sight pipe to cool the detector or to clear a viewing path through UV radiation attenuating material. For a negative pressure combustion chamber, drilling a few holes in the section of the sight pipe outside of the combus- tion chamber will allow air at atmospheric pressure to flow through the sight pipe and into the chamber. A perforated pipe nipple between the sight pipe and the detector can also be used. For a positive pressure combustion chamber, connect a supply of pressurized air from the burner blower to flow through the sight pipe and into the chamber. The air pres- sure must be greater than the chamber pressure. Swivel Mount (C7061A only) To facilitate proper flame sighting, use part no. 118367A Swivel Mount (not supplied). The swivel mount requires a reducer of the proper size to mount it onto the sight pipe. It also requires a one-inch close nipple for mounting to a C7061 with a one-inch connector. (For 118367A Swivel Mount mounting details, refer to form 60-0361). Antivibration Mount The detector withstands normal burner vibration. If the vibra- tion is excessive, part no. 123539 Antivibration Mount is available. (For mounting details, see form 60-0361). If you use this mount, install it before positioning and sighting the detector. Mount the Detector Mount the detector onto the sight pipe, reducer, or other fit- ting. The C7061A/F Self-Checking flame detectors incorpo- rate an oscillating shutter mechanism and, therefore, require special consideration for mounting positions other than ver- tically sighting downward or upward, as illustrated in Fig. 6. The C7061A/F has notch and arrow indicators (see Fig. 7 and 9) on the faceplate to facilitate mounting in positions other than those shown in Fig. 7. The notch and arrow must be vertically aligned with the notch in the up position and the arrow pointing downward (see Fig. 7). The C7061A/F must be mounted with the conduit opening located approximately 45 degrees below the horizontal (see Fig. 7). Fig. 5. Typical mounting of C7061A/F
9 EN1C-0015SZ20 R0314 IMPORTANT The notch and arrow on the faceplate must be aligned in a vertical plane with the notch up and the arrow pointing down. The housing must be mounted with the conduit opening approximately 45° below horizontal (see Fig. 7) To mount a C7061A (Fig. 8): A The mounting flange is in two pieces. Loosen (but do not remove) the three screws holding the flange together. B Slightly rotate the detector so the slots in the back sec- tion of the mounting flange clear the screws in the front section; then separate the two sections. C Screw the front section of the mounting flange onto the sight pipe, reducer, or other fitting. D Fit the slots in the back section of the mounting flange (with the detector) over the three screws in the front section, and rotate the detector so the screws hold the flange together. E Tighten the screws securely. IMPORTANT The rivit on on the faceplate must be at the top (see figure 9). The C7061F can be mounted with increments of 120°. The C7061F has a rivet on the blank alurninium holder. The cell must be positioned so that this rivet is at the top of the installed cell. In certain applications the sensor must be turned in order accoomplish this. To turn the C7061 (Figure 9). A Loose the 3 screws between the pipe connection and bottom part of. B Turn the C7061F in the most favorable position. C Tighten the screws securely. Fig. 6. Vertical mounting of C7061A/F Fig. 7. C7061A mounting Positions Fig. 8. Mounting the C7061A detector Fig. 9. Mounting the C7061F1xxx detector
EN1C-0015SZ20 R031410 WIRING CAUTION When using a C7061A/F with an R7061 or R7861 Dynamic Self-Check amplifier, be careful not to short the white shutter lead wires together (by wiring incorrectly, leaving an incorrect jumper wire, or stripping the insulation too muc h so the bare lead wires can touch). If the shutter leadwires are shorted during the operation, the amplifier can be permanently damaged and nonoperative. 1. All wiring must comply with applicable local electrical codes, ordinances, and regulations. Use NEC class 1 wiring. 2. Keep the flame signal lead wires as short as possible from the flame detector to the ter- minal strip or wiring sub base. Capacitance increases with lead wire length, reducing the signal strength. The maximum permissible lead wire length depends on the type of lead wire and conduit type and diameter. The ulti- mate limiting factor in flame signal lead wire length is the signal current. 3. The C7061A1004 detector has color-coded plastic-insulated, no. 18 lead wires, 8 ft (2.4m) long, rated for 105°C (221°F). These wires must be run in a conduit. 4. If the lead wires are not long enough to reach the terminal strip or wiring sub base, make the required splices in a junction box. 5. If splicing is necessary, use moisture-resis- tant no. 14 wire suitable for at least 75°C (167°F) if the detector is used with a flame safeguard primary control, or at least 90°C (194°F ) if used with a flame safeguard pro- gramming control. 6. For high temperature installations, use Hon- eywell specification no. R1298020 wire or equivalent for the F lead wire. This wire is rated up to 204°C (400°F) for continuous duty. It is tested for operation up to 600 volts and for breakdown up to 7500 volts. For the other lead wires, use moisture-resistant no. 14 wire selected for a temperature rating above the maximum operating temperature. 7. Refer to Fig. 10. for wiring connections IMPORTANT Do not run the flame detector wiring in the same conduit with high voltage ignition transformer wires. Connecting Detectors in Parallel For a flame that is difficult to sight, using two parallel C7061 flame detectors reduces nuisance shutdowns. If only one of the parallel detectors loses the flame signal, the other indi- cates the presence of the flame and keeps the burner run- ning. If two parallel C7061A setectors are used, a flame- simulating failure in either detector causes the burner to shut down. Two C7061A setectors can be connected in par- allel to the same terminals on 120 volt flame safeguard con- trols. CAUTION When using the C7061 in conjunction with an R4348 flame relay at 230VAC, parallel sensores can not be used. To avoid exceeding the rating of the solid-state shutter switch in the R7861 flame signal amplifier, do not connect more than two C7061A detectors in parallel. IMPORTANT Voltage and frequency rating of the C7061A must match the power supply of the flame safe- guard control. Fig. 10_1. Wiring diagram for C7061A1004 detectors with 7800 SERIES Flame Safeguard controls with shut- ter drive circuitry. Fig. 10_2. Wiring diagram for C7061A1004 detector with R4348 Flame Safeguard controls with shutter drive circuitry.