IRIS S550 Applications Manual Download Page 9

viewing head sight path will greatly improve the
performance, particu larly with regard to discrimi 

-

nation between flames. Although saturation is less 
likely with the Ge (germanium) IR photo de tector
used for the S550 as compared to prior model
viewing heads using the PbS (lead sulfide) type
photo de tector, the possi bility should not be
ignored. Saturation is more prob able with large
power utility boilers where the burners are very
large and relatively close to one another. If one
cannot look at the flame with the naked eye
without it hurting, then orificing should be used.
This eye test works for incan descent type flames
such as oil and coal but will not be valid for
natural gas flames.

Orificing may help improve the discrimi nation
charac ter istics for the UV detector as well as the
IR. The UV tube in the S550 is not likely to
saturate; how ever, orificing will usually improve
the discrimi nation ratio for large size burners.

An orificing disc is simply a metal disc with a
circular hole in the cen ter which is placed directly
in front of the lens. Four orificing discs are
available with cen ter hole diameters of 3/8, 1/4,
3/16 and 1/8 inch. These discs are installed with
retaining rings in the flange at the edge of the 1/2
inch NPT female pipe thread for the purge air. An
internal type retaining ring is first installed by
positioning a ring in the machined groove inside
flange opening from the housing side. The
orificing disc is then inserted. Use a second
retaining ring to hold it in place so that it is
sandwiched tightly between the two retaining
rings.

Usually an orificing disc with a larger diameter
hole is tried first. There will be a reduction in the
signal level so if the associated S550 and signal
processor has been previ ously calibrated it will be
necessary to calibrate the processor again so that
the gain settings will be correct. If the discrimi 

-

nation is still not satis factory then try an orificing
disc with a smaller diameter hole.

Generally speaking,  orificing should always be
considered when the burner(s) are large (50K lbs
of steam and up), particu larly when the IR

detector is used which would be the case for oil or
pulverized coal.

The following table shows the signal reducing
charac ter istics of the different orificing discs:

Ap er ture

Hole

Fn

(f Stop)

Rela tive light

pass ing power

1"

2

1

3/8"

5.3

1/8

1/4"

8

1/16

3/16"

10.7

1/32

1/8"

16

1/64

DEFAULT SETTINGS FOR THE S550

A new P520 / P522 will send the S550’s default
“Gains” as follow:

UV Gain = 32

(out of 0-99 range)

Fil ter = Fil ter  3 (high pass above 33Hz)

IR Gain = 451

(out of 0- 699 range)

These are nominal settings that should allow for
initial sightings and adjust ments. Both UV and
IR sensors are active in the default mode
. They
are the same settings that will be active in an S550
when used with an older version of the P520/P522
or with an M502 signal processor. If the settings
for the S550 have been changed from the default
settings the operator may reset the “Gain” to the
factory default from the P520 / P522 control
panel. (See 

Return to Default Settings

 on Page 12.)

WHERE S550 SETTINGS ARE STORED

Settings for the S550s are stored in EEPROM in
the particular P520/P522
 which made the adjust 

-

ments. On subse quent power-up cycles the
P520/P522 will send out the settings again to the
S550 viewing head. In fact, if one S550 is
exchanged with another one, the P520/P522
cannot tell one S550 from another and will send
out the same settings. This simplifies field
replace ments; all S550’s are made to very close

PAGE 9

IRIS MODEL S550 APPLICATION MANUAL

Summary of Contents for S550

Page 1: ...PAGE 1 IRIS MODEL S550 APPLICATION MANUAL FLAME MONITORING SYSTEM MODEL S550 S552 S556 VIEWING HEAD APPLICATION MANUAL ...

Page 2: ... ARE STORED 8 ASSIGNING DIFF S550 SETTINGS TO A B 9 USING TWO VIEWING HEADS PER AMPLIFIER 9 BEFORE MAKING ADJUSTMENTS 10 NEW P520 P522 FRONT PANEL 10 CALIBRATING THE S550 10 EXAMINING RESULTS GAIN SETTINGS CALIB 10 CHECKING OR CHANGING UV GAIN 11 CHECKING OR CHANGING IR FILTER 11 CHECKING OR CHANGING IR GAIN 11 MANUAL SETUP OF THE S550 12 RETURN TO DEFAULT SETTINGS 12 ANGLE OF VIEW 13 GENERAL COMM...

Page 3: ...Filter Selection 1 8 b IR gain 0 699 When it comes to features like CAL which will be described later the operator is only given those choices which are appropriate For example he does not have to choose between calibrating with the UV sensor or the IR sensor in CAL he is only offered the choice of calibrating with the IR sensor or not This is shown in the FLOWCHART OF S552 PROGRAMMING Figure 4 on...

Page 4: ...processors Also the earlier IR sensitive family members had only 4 high pass filters to choose from the S550 has 8 S511 S512 S550 LL 36 Hz 1 16 Hz L 71 Hz 2 24 Hz M 105 Hz 3 33 Hz H 186 Hz 4 52 Hz 5 75 Hz 6 100 Hz 7 155 Hz 8 215 Hz TECHNOLOGY USED IN THE S550 The UV and IR sensors in the S550 share a common optical axis efficiently by using a unique dichroic beamsplitting mirror Over 80 of the ult...

Page 5: ...PAGE 5 IRIS MODEL S550 APPLICATION MANUAL ...

Page 6: ...e done as follows Remove the plug from its packaging and layout the components 1 Strip 2 inches of the cable outer cover from the cable removing any cellophane wrap or filler material and strip the insulation from the shielded wire if insulated over shield a full 2 inches to expose shield 2 Slide the shield back until a bulge develops close to where the wire exits the cable outer covering 3 Carefu...

Page 7: ... entirely The reason for this is that there is a complete change in the flicker content for the existing viewing head sighting If this is the case then one should try and optimize the flame signal for the sour gas by zeroing in on this flame not the warm up burner After optimizing the sighting for the sour gas one may find that the signal level is too low on the natural gas One should then try the...

Page 8: ...ition the zone of higher UV intensity does not overlap the same zones of adjacent or opposing burners so that with proper sighting discrimination is predictable As a general rule the sighting of the S550 when using the UV detector will be more likely a line of sight than the IR flicker detector which will read flame signals bouncing off the side of the sight pipe and other reflectors Sometimes the...

Page 9: ...n the signal level so if the associated S550 and signal processor has been previously calibrated it will be necessary to calibrate the processor again so that the gain settings will be correct If the discrimi nation is still not satisfactory then try an orificing disc with a smaller diameter hole Generally speaking orificing should always be considered when the burner s are large 50K lbs of steam ...

Page 10: ...manually changing S550 settings when the desired channel is not selected press the push button for the desired channel and then proceed During the process of examining or changing the S550 settings with the Channel A and B NO and YES push buttons the red LED for the channel which the changes apply will be blinking One should visually check which channel push button is lighted when the S550 setting...

Page 11: ...ture one does not have the option of working with the channel that is not selected by the external input 3 Bring the firing rate of the burner to a low fire condition 4 If the flame relay has not pulled in adjust the flame on off set points so it does pull in 5 Decide whether to calibrate using the UV or IR sensor See earlier sections on I R DETECTOR and UV DETECTOR At the front panel of the P520 ...

Page 12: ...r all of the initial setup proce dures described in this manual Further infor mation on how these filters can affect the discrimi nation ratio is found in the P520 APPLICATION MANUAL and in the P522 APPLICATION MANUAL in the section MULTIBURNER REQUIREMENTS For further information please call the factory or contact IRIS Systems Inc See page 13 for contact information CHECKING OR CHANGING IR GAIN Y...

Page 13: ...tinue reducing the gain in steps of 100 until the displayed reading is reduced Then set the gain so the reading is in the 1000 to 1400 range If the IR sensor was not saturated one can skip paragraph 5 below 5 If the S550 was saturating one should check the aiming of the S550 again using the LED on the back of the housing to adjust the viewing angle of the head for a maximum pulse rate If the LED p...

Page 14: ...vative product that this is the ultimate state of the art flame monitor The way it works has been described only in a general sense and obviously the algorithms implemented by the embedded controller software are proprietary and will not be made public Any existing P520 or P522 signal processor can be upgraded to an S550 compatible processor by changing the controller chip and the front panel TECH...

Page 15: ...PAGE 15 IRIS MODEL S550 APPLICATION MANUAL Figure 1 Figure 2 ...

Page 16: ...IRIS MODEL S550 APPLICATION MANUAL PAGE 16 Figure 3 ...

Page 17: ...PAGE 17 IRIS MODEL S550 APPLICATION MANUAL Figure 4 ...

Page 18: ...PAGE 18 IRIS MODEL S550 APPLICATION MANUAL Figure 5 ...

Page 19: ...PAGE 19 IRIS MODEL S550 APPLICATION MANUAL 5 June 1997 ...

Reviews: