Operation; Ir Detector; Uv Detector; Filter Selection For Ir Viewing Head - Honeywell 700 User Manual

Insulating locking coupler adapters (R-518-PT13, R-518-
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 (ASY784) - Replacement quick disconnect
connector for all S70X/S80X models.
Connector + Cable (ASY782) - Replacement pre-assembled
15-foot (4.7m), 4-conductor cable (C330) with quick
disconnect (ASY784) for all S70X/S80X non-pipe fitting
models. There are also five more pre-assembled cable and
connector assemblies available; ASY782-030 (30ft/9m),
ASY782-050 (50ft/15m), ASY782-100 (100ft/30m), ASY782-
200 (200ft/61m) and ASY782-250 (250ft/76m).
Cable (C330) - 4 conductor cable with 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.
Liquid tight cable adapter (700LTA) - S70X/S80X viewing
head cable adapter with 3/8 in. NPTF conduit connection.
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.
Vortex coolers (M3204, M3208, M3210, M4025) - Used with
air cooling canister. Contact your distributor or the factory for
selection assistance.
Cable restraints (800CR, 700CRLT) - Liquid tight S80X and
S70X cable restraint versions. The 800CR includes the
700CRLT and the 800ACC-RING adapter.
S80X adapter ring (800ACC-RING) - Adapter ring to fit S80X
viewing heads to 700ACC cooling jacket and 700CRLT liquid
tight cable restraint.
Right angle adapter (700RAA) - S70X/S80X viewing head
right angle adapter. 1/2 in. NPTF to 1/2 in. NPTM connections.
Mounting blocks (700DA, 700DA-1, 800DA) - Delrin
replacement adapter/mounting blocks for S70X and S80X
viewing heads. All have 1/4 in. NPTF purge air connections.
Rated for continuous service up to 180F (82C). The 700DA
and 800DA have 1/2 in. NPTF process connections while the
700DA-1 has a 1 in. NPTF process connection. For more 1 in.
NPT accessories that can be used with the 700DA-1, refer to
the S55XB/BE manual, 66-2064.
USB to RS422/RS485 Converter (COMMOD) - Protocol
converter for use with external communication with a remote
computer.
Fiber Optic System Compatibility - The S70X and S80X
viewing heads are compatible with the Honeywell FASA fiber
optic extension products. The S700FOAD and S800FOAD
HONEYWELL MODEL 700/800 SIGNAL PROCESSOR AND VIEWING HEAD
adapters are applicable, depending on the application.
Contact your distributor or the factory for assistance with fiber
optic selection and pricing.

OPERATION

IR Detector

The S702 and S802 viewing head models use a Germanium
photodiode, which responds to IR radiation/flicker in the flame.
Flame flicker is caused by the combustion, or forced air
injected in to the flame. Combustion air can be mixed with the
fuel (pulverized coal) or can be introduced separately. In either
case, forced air is introduced in such a way as to aid the
combustion process. This air is usually made turbulent by
causing it to swirl with spin vanes located in the burner throat.
Flame flicker is created when turbulent air mixes with the
flame. It is composed of random frequencies and the amount
of high frequency flicker is dependent on the fuel and the
burner.
The S702, S702PF and S802 viewing head models respond
to flicker frequencies above 33Hz while the S702HF,
S702HFPF and S802HF viewing heads respond to flicker
frequencies above 155Hz. All flicker frequencies below the
filters are ignored, so it is important to sight the viewing head
on the highly turbulent portion of the flame that contains the
higher frequencies. The location of the higher frequencies can
be predicted by examining the burner with regard to where the
turbulent air enters the flame. The optimum scanner location
is parallel to the burner center line (Fig. 14). The use of a
swivel mount is encouraged to allow for line of sight.

Filter Selection for IR Viewing Head

If a good count ratio between BNR-ON and BNR-OFF cannot
be obtained when using an IR viewing head—particularly
when monitoring oil flames—an IR viewing head with the High
Frequency (HF) filter option is recommended. The standard IR
viewing head responds to flicker frequencies above 33 Hz;
with the HF option, the IR viewing head responds to flicker
frequencies above155 Hz.

UV Detector

The S706, S706PF and S806 viewing head models use the
UVTron tube, with a spectral response of 185-260nm and
peak response of 210nm to ultraviolet radiation. The output of
the detector is a pulse stream of randomly spaced pulses
whose average rate is proportional to the UV radiation present
in the flame. The UV radiation is a direct result of the
combustion process as oxygen combines with hydrocarbons
in the fuel in the blue part of the flame. The yellow part of
flames, and the background radiation from hot refractory, do
not emit UV radiation.
The spectral range of the UV tube makes it ideal for
discriminating between flame and glowing refractory. As with
any UV radiation, it can be absorbed or masked by unburned
fuel, smoke, oil mist, dirt dust and other impurities in the fuel.
Care should be taken to select the proper viewing head for the
fuel used. Additionally, the contaminants that mask UV can be
diluted by providing a strong flow of air through the sight pipe
to clear a viewing path through the attenuating material. See
"Purge Air" on page 10.
11 66-2069—01