Fireye PPC6000 Series, Operator'S Manual

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18
Fault
Number Cause Description
F78 Secondary program
memory checksum
fault A fault has occurred with the program memory in the control. If
the fault persists for 11 consecutive tests then the burner will
shutdown.
x
Contact supplier
Subset : Not applicable.
F79 Secondary
watchdog fault A fault has occurred with the CPU watchdog. If the fault persists
for 11 consecutive tests then the burner will shutdown.
x
Contact supplier
Subset :
1 = Late test failed.
2 = Early test failed.
10 PID Tutorial
PID Adjustment
The PPC6000 utilizes and advanced algorithm in order to maintain set point over a variety of load conditions.
This three term PID can be infinitely adjusted to suit almost any application. The operator should have a basic
understanding of the relationship between the three terms; proportional, integral and derivative.
Proportional
Typical older modulating systems employ only proportional control. This would be similar to the slide wire type
found on most steam boilers. When using only a proportional control the system rarely achieves set point as
the burner firing rate is lowered as the pressure comes up. At some point the input meets the actual demand
and the pressure no longer raises or lowers, thus an offset between desired set point and actual operating
pressure occurs. The only time the pressure and set point are the same is if the actual load equals the lowest
firing rate of the burner, this is rare. An example of proportional only set up might be; Set point is 100 PSI,
proportional range is 10 PSI. That is low fire is at 100 PSI, high fire is at 90 PSI with a 1:1 relationship in
between, e.g.: 95PSI equals 50% rate.
Integral
If the integral term is turned on, the control compares the actual pressure against set point at an adjustable
interval. If there is an offset, the firing rate is increased by a small percentage until the next interval. This will
continue until the pressure equals the set point. The same routine occurs as the pressure rises above the set
point. Too much or too little integral will cause over and undershoot of the set point. Integral is set in second
per repeat in the PPC6000.