Honeywell 700 User Manual

9

66-2069—02

position has been decided. A continuous flow of air must be 

maintained in order to reduce the conducted heat and to keep 

the sight pipe and viewing head lens free of dirt and debris. Air 

required is about 5 SCFM (0.13 Nm3 /min) delivered at 1 in. 

(25mm) above the maximum pressure as measured at the “Y” 

or “T” section of the purge air connection for each viewing 

head. The air supply must be clean, free of oils and water, and 

preferably cool. In order to electrically isolate the viewing 

head, the purge air line should be installed using an insulating 

material, such as a rubber hose, in between the purge air line 

and the viewing head.

Do not install the viewing head where it could be subject to 

high vibration. Provide an anti-vibration mount if excessive 

vibrations are present.

Make sure there will be sufficient room to remove the viewing 

head housing for servicing.

Honeywell offers a range of swivel mounts, both pipe thread or 

flange mounting for use with sight pipes or direct wind box 

mounting. See “Accessories” on page 9 or the Honeywell 

website for further details.

The sighting of the viewing head should be parallel to the 

center line of the burner in the direction of the flame. If used, 

the sight pipe should be mounted as close to the center line 

as possible so as to sight along the flame rather than across 

the flame. Doing so will ensure continuous flame detection 

under changing load conditions. See Fig. 15, 16 and 17.

Utilizing a sighting or the sight pipe aimed at the root of the 

flame (where the turbulent combustion air mixes with the 

flame) is a good starting point for optimizing the sighting. 

Where practical, using a swivel mount to “zero-in” on the 

highest signal will assure maximum performance. The 

optimum scanner location is parallel to the burner center line. 

The use of a swivel mount allows for line of sight adjustment, 

where practical to use.

Examples of viewing head installation with and without a 

swivel mount are shown in Fig. 13 and Fig. 14. If using a sight 

pipe, its diameter should be large enough to allow a 

reasonable field of view, and to allow for adjustment of the 

swivel mount angle.

In some instances, it may be beneficial to use two sets of 

setpoints for Flame On, Flame Off and gain. The two-channel 

capability (primary and alternate viewing head settings) is 

ONLY possible when using the P531 or P532 signal 

processors; it is not possible when using the 700ACSP or 

700DCSP signal processors. The switch-over from Channel A 

to Channel B can be implemented from the burner control 

system. Refer to the P531/P532 user manual, 66-2068, for 

further information regarding switch-over and the use of 

Channels A and B with independent settings.

Orifice disks (kit M-702-6) - Used to reduce the signal 

brightness in cases where the signal brightness is too strong. 

Located immediately in front of the lens, it will reduce the 

amount of signal to the sensor. Bag assembly contains orifice 

disks and retaining rings. Orifice disks come with 3/8, 1/4, 

3/16 and 1/8 inch diameter holes. Contact the factory for 

guidance in using orifice disks.

Insulating nipple (R-518-13) - 1/2-in. NPTM Ultem heat and 

electrical insulating nipple typically used in conjunction with a 

swivel mount and union.

VH insulating mounting block (700UA, 800UA) - 1/2 in. 

NPTF Ultem heat and electrical insulating mounting block, 

used in place of the supplied Delrin mounting block. 1/4 in. 

NPTF purge air connection. Typically used in conjunction with 

a swivel mount. Rated for continuous service up to 320°F 

(160°C).

Swivel mounts, small (700-1, 700-2, 700-3) - All have 1/2 in. 

NPTM viewing head connections on one end with varying 

process connections including 1 in. NPTF, 1/2 in. NPTF and 

1/2 in. flanged.

701-2-SS, M-701-3, M-701-3P, M-701-4) - All have 1 in NPTF 

viewing head connections, one end with varying process 

connections including 2 in. pipe slip on, 2 in. NPTF, 2 in. 

flanged, 2 in. NPTF in stainless steel construction, 4.5 in. 

flanged with 3 bolts, 3 in. NPTF and 2-bolt flanged.   

Appropriate fittings must be used to adapt the 1/2 in. NPTF 

viewing head process connections.

PT13L) - 1/2 in. NPTM Ultem adapters insulate the viewing 

head electrically and thermally and are used with the R-518-

CL13-HTG locking couplers. The R-518-PT13L has a quartz 

lens.

Locking coupler (R-518-CL13-HTG) - Used with the R-518-

PT13 and R-518-PT13L insulating locking coupler adapters. 

Process connection end is 1/2 in. NPTF.

Connector - ASY786 --> Replacement field wireable

 

connector.

Cable and Connectors - S70X/S80X Viewing Heads 

ASY785 --> 50 foot C330S cable with pre-wired ASY786 

connector.

ASY785-200 --> 200 foot C330S cable with pre-wired ASY786 

connector.

Cable (C330S) - 4-conductor with drain, foil/braided shield. 

Sold per foot. 

Isolation Units (ISO-UNIT, ISO-UNITSS, ISO-UNITHPGT) - 

All have 1 in. NPTF connections with 1/2 in. NPTF purge ports 

and quartz window. Painted aluminum or stainless steel 

construction. The HPGT version has a 1/2 in. thick quartz 

window for higher pressures. Appropriate fittings must be 

used to adapt the 1/2 in. NPTF viewing head process 

connections.

Air cooling canister (700ACC, 800ACC) - Has an air inlet 

port on side. Used with vortex coolers. S80X models can be 

used with the 700ACC if the 800ACC-RING adapter is used.