CleaverBrooks CBEX Elite, Эксплуатация и обслуживание

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Adjustment Procedures
6-8 750-368
CBEX Elite 100-1200 HP
The adjustment must be accomplished within the time limit of the safety switch or approximately 30 seconds
after the detector is removed. If the control shuts down, manually reset it. Replace the detector and repeat the
process from step 5.
7.
When a suitable flame as indicated in step 6 is obtained, replace the detector. Observe the reading on the
micro-ammeter. The reading should be between 2-1/4 and 5 micro amps when using a lead sulfide detector
and a standard amplifier. See the flame signal table in the manufacturer’s bulletin for values of other combi-
nations.
The flame signal indicated on the annunciator type relay should not be less than 5 Vdc, and may be as high
as 20 Vdc or greater.
The reading must be steady. If the reading fluctuates, recheck the adjustment. Be sure that the flame detector
is properly seated and that the lens is clean.
8.
Return the Run/Test switch to the “Run” position.
9.
If main flame has not been previously established, proceed to do so in accordance with instructions elsewhere
in the manual.
10.
The reading of the main flame signal should also be checked. Observe the flame signal for pilot alone, pilot
and main burner flame together and the main burner flame at high, low, and intermediate firing rate positions.
Readings should be steady and in the range indicated in step 7. If there are any deviations, refer to the trou-
bleshooting section in the technical bulletin.
6.11 — Gas Pressure and Flow Information
Because of variables in both the properties of gas and the supply system, it will be necessary to regulate the
pressure of the gas to a level that produces a steady, dependable flame that yields the highest combustion effi-
ciency at rated performance yet prevents over-firing. Once the optimum pressure has been established, it should
be recorded and periodic checks made to verify that the regulator is holding the pressure at this level. Occasional
modification in fuel composition or pressure by the supplier may, at times, require readjustment to return the
burner to peak efficiency. Since the gas pressure regulator itself is usually furnished by others, detailed adjust-
ment instructions and adjusting procedures recommended by the manufacturer should be followed.
6.11.1 — Pressure
The gas supplied must provide not only the quantity of gas demanded by the unit, but must also be at a pressure
high enough to overcome the pressure loss due to the frictional resistance imposed by the burner system, control
valves, and piping.
The pressure required at the entrance to the burner gas train for rated boiler output is termed “net regulated pres-
sure.” The gas pressure regulator must be adjusted to achieve the pressure to assure full input.
The pressure requirement varies with boiler size, altitude, and type of gas train. Refer to Table 6.1 for pressure
requirements.
When checking the pilot flame, be aware the electrode is energized. Failure to follow these instructions could result in
serious injury or death.
!
Warning