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T-Product · BCU 465 · 2006 April
Operation
1400 °F (750 °C) Auto Ignition
Flame Management Bypass
Input
A digital contact “D1”, if used, allows
the Burner Control Unit “BCU” flame
amplifiers to be bypassed if the proc-
ess temperature is above the auto ig-
nition temperature of the fuel. This is
typically 1400 °F (760 °C). A suitable
“FM” approved low limit controller must
be used to supply the digital input
“D1”, terminal #6. Consult local regu-
latory agencies and your insurance
underwriter for additional safety re-
quirements and approved controllers.
See also Safety Considerations.
If the “D1” input is used, parameter 33
must be configured for desired opera-
tion of the BCU.
If parameter 33 = 2, the BCU will shut
down the burner and restart when
the high temperature operation has
ended. This is recommended if UV
flame detection devices are used.
If parameter 33 = 3, the BCU will
continue normal operation after the
process temperature has dropped
below the auto ignition temperature.
The flame signal will now be monitored.
This is recommended if flame rods are
used.
