41
®
If the automatic trim commissioning is performed, the engineer
MUST CHECK THAT THE VAL-
UES ENTERED ARE VALID AND SAFE AFTER COMPLETION.
Additionally, the oxygen
probe calibration should be checked before and after the procedure since the results are highly
dependent on measurements taken using the probe.
Entering the Option Parameters
With the burner off, enter commission mode. To get the trim operational it is only necessary to set up
the following option parameters:
1. Trim drive – The drive moved in order to achieve trim (options 32.X)
2. Trim limits – To impose limits on the amount of trim applied (options 33.X)
3. Trim enable – To turn trim on (option 35.5)
Before proceeding to enter the oxygen setpoints for each profile, a few points relating to the oxygen
trim option should be considered.
•
The drives being trimmed
must not
be selected as
lead drive
.
•
No trim is applied which would require a drive to move above its high fire position or below its
low fire position.
•
The flow for each profile position must be entered to ensure correct operation. The flow can
either be measured for each profile position or calculated as a percentage with respect to the
flow at high fire.
Using Adjust Ratio Mode to Enter Oxygen Setpoints and Flow Values Manually
When using the adjust ratio mode, it is not possible for the unit to check drive positions at all times.
It is the responsibility of the engineer to check that motors and valves are responding correctly.
To adjust an oxygen setpoint or enter an air flow value in the firing range, use the following proce-
dure. The manual calculation of the values to be entered here is covered in the next section.
1.
Enter adjust ratio mode.
2.
Ensure oxygen trim or monitoring is selected by option parameter 30.0 (1 or 2).
3.
Use the scroll keys to select the desired setpoint and move up and/or down (A4 for example).
The system will modulate to the selected setpoint and the number displayed will flash to indi-
cate that the drives are modulating.
4.
Wait for the number in the display to be illuminated steadily. This means that the drives have
arrived at the selected setpoint.
5.
The display will allow scrolling sideways to show flow and "o2" in addition to the servo-motor
positions to indicate that the system is expecting a flow value and an oxygen setpoint to be
entered for the current profile setpoint. To check the current oxygen measured value use the
engineer’s key facility.
6.
Once the oxygen value is shown on the display use the scroll keys to position the ‘>’ pointing to
the ‘o2’ value use the UP/DOWN keys to adjust the oxygen setpoint as necessary. The display
will start flashing to indicate that a change has been made.
7.
If the new oxygen setpoint value is wanted, press the ENTER key. The value will be stored in
memory.
8.
If the new oxygen setpoint value is not wanted or an adjustment is not required, press the NEXT
key to return to the value stored in memory.
9.
Once the flow value is shown on the display use the scroll keys to position the ‘>’ pointing to
the ‘FLO’ value use the UP/DOWN keys to adjust the flow value as necessary. The display will
show the air flow value, represented as a percentage of the air flow when the drives are at the
HIGH FIRE position. The display will start flashing to indicate that a change has been made.
10.
If the new flow value is not wanted or an adjustment is not required, press the NEXT key to
return to the value stored in memory.
11.
If it is necessary to adjust another setpoint in the firing range, repeat the above procedure from
step 3.
