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Chapter 5. Trial Operation and Adjustment
Measurement of flame voltage
This device shows the flame voltage on the 7-segment display. It can be checked by
changing the display using the DISP switch on the front of the device.
Checking the flame voltage is the best way to determine whether or not the location
of the flame detector is appropriate.
It should be checked during installation and servicing.
Checking it once per month or more can prevent shutdowns due to insufficient flame
voltage.
Start the device and measure the voltage under various conditions, such as at
startup and during normal operation.
Check to make sure that the flame voltage remains stable at 2.0 V DC or more. The
recommended flame voltage is 2.0 V DC or more and it must be stable.
* If this stable voltage cannot be achieved, the problem may be caused by one or
more of the following. In such a case, do a thorough inspection.
•
The power supply voltage or frequency is not correct.
•
The air supply pressure or air-fuel ratio is not correct.
•
The flame detector is not correctly wired.
•
Open circuit
•
Short circuit
•
High-resistance short circuit of the lead wires due to the temperature or dirt
•
Incorrect flame detector mounting angle (AUR890G)
•
Dirty flame detector sensing surface (AUR890G).
•
AUD15C tube unit deterioration (AUR890G).
•
Incorrect flame rod installation (AUR890G).
•
Area in contact with flame is insufficient.
•
Position of flame rod in flame is incorrect.
•
The flame rod insulator is at a high temperature (315 °C).
•
Flame rod is affected by ignition transformer.
If the ignition transformer is placed close to Terminal F of the flame rod,
electrons in the flame are absorbed into the ignition transformer, and as a
result, sufficient flame voltage cannot be achieved.
Correlation of flame output with that of older model
•
AUR890G (AUD100/110/120)
•
AUR890F (flame rod)
RA890G Current−AUR890G Voltage
0
RA890G
Flame current [μA]
0
AUR890G
Flame voltage [V]
0.5
0.5
1
1.5
2
1
1.5
2
2.5
3
RA890F Current−AUR890F Voltage
0
RA890F
Flame current [μA]
0
AUR890F
Flame voltage [V]
1
1
2
3
4
5
6
2
3
4
5
6
Содержание 81447514-001
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