Azbil AUR450C - Chapter 4: Trial-Run Adjustment; Overview of Adjustment Procedures; Required Tools and Test Equipment

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Chapter 4. TRIALRUN ADJUSTMENT
WARNING
Do not allow the pilot or main burner “Safety time” (ignition trial time) to exceed the specifications
of the burner or equipment manufacturer. If they do, fuel may accumulate in the combustion
chamber and form an explosive airfuel mixture, resulting in a serious explosion hazard.
Terminals and the connected flame detector signal cable retain an electrical charge even after
the power is turned OFF. To avoid electric shock, do not touch terminals F and G or the cable
immediately after power-off.
Do not start regular operation of the equipment without first completing the trial-run
adjustments for this device, as well as the tests specified by the equipment manufacturer.
If lockout occurs, be sure to do a prepurge before restarting the system. If the combustion
chamber and gas flue are not ventilated to remove any unburned gas, the ignition process may
cause an explosion.
CAUTION
Installation, wiring, inspection, adjustment, etc. should be carried out by a trained and
experienced technician who has knowledge and technical skills related to combustion
equipment and flame safeguard control devices.
Only an experienced technician who has knowledge and technical skills related to combustion
equipment and combustion safety should carry out the pilot turndown test.
 Outline of adjustment
The following test adjustment items are described in this chapter:
•
Measurement of flame voltage
•
Pilot turndown test
•
Ignition spark response test
•
Safety shutoff test
Handling Precautions
•
After the above items have been adjusted, check again that each adjust-
ment is satisfactory. It is absolutely necessary for all adjustments to be cor-
rect before the final positioning of the flame detector.
•
Do not repeatedly turn the power supply switch ON and OFF. Doing so may
cause incorrect operation. After turning the power OFF, wait at least 3 sec-
onds before turning it ON.
z Tools and parts needed
•
Multimeter or FSP136A: Input impedance: 100 kΩ or more
AC range: 0 to 300 V
DC range: 0 to 10 V
•
Jumper cables with clips: Two, AWG14 (2 mm
2
) min., approx. 30 cm long
•
Insulation resistance tester: 500 V DC megger