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PRODUCT DATA

65-0267—09

C7961E,F Dynamic Self-Check 

Ultraviolet Flame Detector

APPLICATION

The C7961E,F are dynamic self-checking flame detectors for 

sensing the ultraviolet radiation generated by the combustion 

of gas, oil, or other fuels.

FEATURES

• Oscillating shutter interrupts ultraviolet radiation 

reaching the UV sensor at a 3 Hz rate to provide the UV 

sensor tube checking function. The 7800 Series 

Control conducts an additional shutter test every 5 

seconds.

• Detectors can be mounted horizontally, vertically or at 

any other angle. 

• Quartz viewing window is field replaceable.
• Threaded conduit fitting and color-coded leadwires 

allow rapid electrical installation.

• 3/4 in. and 1 in. NPT mounting models available.
• Models available with Molex Woodhead 

1R5006A20A120 (Formerly

 

Brad Harrison® 41310) 

connector.

• A swivel mount is available to facilitate flame sighting.
• -40°F (-40°C) rated ultraviolet sensing tube.
• Incorporates UV sensor tube checking feature; used 

with R7851C Dynamic Self-check Amplifiers.

• High pressure 50 psi (345 kPa) quartz viewing window, 

magnifying lens and antivibration mount are available 

as accessories.

• Housing meets NEMA 4 enclosure standards (C7961E).
• Protective heat block built into mounting flange.
• C7961E, F are immune to x-ray.

C7961F:

• Housing designed to be explosion-proof and 

Underwriters Laboratories Inc. listed for use in 

hazardous locations; Class I, groups C and D; and 

Class II, groups E, F and G.

• Viewing window rated for 100psi (690 kPa).

C7961F

C7961E

Contents

Application ........................................................................

1

Features ...........................................................................

1

Specifications ...................................................................

2

Ordering Information  ........................................................

2

Installation ........................................................................

3

Wiring (Fig. 10) .................................................................

7

Adjustments and Checkout ...............................................

8

Troubleshooting ................................................................

9

Service ............................................................................. 10

Summary of Contents for C7961E

Page 1: ...Models available with Molex Woodhead 1R5006A20A120 Formerly Brad Harrison 41310 connector A swivel mount is available to facilitate flame sighting 40 F 40 C rated ultraviolet sensing tube Incorporates UV sensor tube checking feature used with R7851C Dynamic Self check Amplifiers High pressure 50 psi 345 kPa quartz viewing window magnifying lens and antivibration mount are available as accessories ...

Page 2: ...ets NEMA 4 enclosure requirements indoor outdoor pro tection rain tight dust tight hose directed water protec tion C7961F Explosion proof two piece violet cast aluminum Pressure Rating of Quartz Viewing Window C7961E 20 psi 138 kPa see Replacement Parts C7961F 100 psi 690 kPa Pressure Rating of Quartz Focusing Lens 20 psi 138 kPa see Accessories Mounting C7961E Mounting flange with 3 4 in NPT or 1...

Page 3: ...lues marked on the detector 4 Sight the detector so it does not respond to ignition spark 5 On multiburner installations each detector must respond only to the flame of the burner it is supervis ing Proper flame detector installation is the basis of a safe and reliable flame safeguard installation Refer also to the burner manufacturer instructions Carefully follow all instructions for the best pos...

Page 4: ...ge of the detector field of view If the temperature of the hot refractory causes the flame relay in the flame safeguard control to pull in re aim the sight pipe so the detector views a cooler area of the refractory Ignition spark is an intense source of ultraviolet radiation When installing the detector make sure it does not respond to ignition spark Single Burner Requirements The detector must ha...

Page 5: ...an installation locate each flame detector so that it has the best possible view of the first 30 percent closest to the burner nozzle the flame root it is supervising and the worst possible view of all other flames Fig 4 illustrates a critical detector application problem that requires flame discrimination Flame discrimination is accomplished for Detector A by repositioning it until the flame rela...

Page 6: ...the sight pipe and into the chamber The air pressure must be greater than the chamber pressure Swivel Mount To facilitate proper flame sighting use 118367A Swivel Mount ordered separately 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 C7961 with a one inch connector For 118367A Swivel Mount mounting ...

Page 7: ...ectrical ignition source in the event of a seal leakage 1 All wiring must comply with applicable local electrical codes ordinances and regulations Use NEC Class 1 wiring 2 Keep the flame signal leadwires as short as possible from the flame detector to the terminal strip or wiring subbase Capacitance increases with leadwire length reducing the signal strength The maximum permissible leadwire length...

Page 8: ...e when using direct spark ignition Also measure the flame signal at low and high firing rates and while modulating in between as applicable With the detector in its final position all required flame signals must be steady or stable and as specified in Table 1 If you cannot obtain the proper signal refer to the Troubleshooting section Pilot Turndown Test When the detector is used to prove a pilot f...

Page 9: ...satisfactorily completed TROUBLESHOOTING WARNING Electrical shock hazard Can cause serious injury or death Open the master switch to disconnect power before removing or installing the detector or its cover More than one disconnect may be involved Equipment Required A volt ohm meter with a minimum sensitivity of one megohm volt and a zero to five or ten Vdc scale is suggested When the Keyboard Disp...

Page 10: ... place to avoid losing them Fig 12 Replacing quartz viewing window or focusing lens Replacing Quartz Viewing Window or Focusing Lens C7961E Fig 12 IMPORTANT Use quartz window or lens Ordinary glass absorbs or filters out ultraviolet radiation 1 Open the master switch remove the detector from the sight pipe and remove the detector cover See appropri ate sections 2 Loosen the three screws holding th...

Page 11: ... to the faceplate and remove the flange Put the bolts in a safe place 3 Unscrew the retaining ring with its rubber O ring seal from the seal off flange 4 Tip the flange and let the viewing window fall into your hand 5 Insert either side of the new 122037 Quartz Viewing Window into the window aperture 6 Screw the retaining ring with O ring seal into the seal off flange and tighten securely 7 Clean ...

Page 12: ...DETECTOR Automation and Control Solutions Honeywell International Inc 1985 Douglas Drive North Golden Valley MN 55422 customer honeywell com U S Registered Trademark 2013 Honeywell International Inc 65 0267 09 JPG Rev 01 13 Printed in United States ...

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