37
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2.
P-HOLD
– When this input is active (energized), the BurnerLogix system will hold in the pilot
stage during start up and will only advance to MTFI when the input is de-energized.
3.
I-HOLD
– When this input is active and if the firing state is AUTO, the BurnerLogix system
will drive the firing rate to 0% and hold the burner in the low fire position.
4.
PROCESS
– When this input is active (energized), the BurnerLogix will operate in the follow-
ing manner:
a.
During burner start up, the BurnerLogix system will hold in the pilot stage during burner
start up. De-energizing the input (terminal 21) will force the unit through MTFI back
into the AUTO position.
b.
While in the AUTO or main firing position, this input will force the BurnerLogix system
to drop back to the pilot hold stage by first dropping back to the low fire position,
proving the M-D low fire start input, energizing the pilot valve and ignition transformer
and after a stabilizing delay of 20 seconds, de-energize the main valve and do a PTFI
sequence in accordance with the PTFI*MTFI TIMING selection. After PTFI, the system
will remain in the pilot hold mode with only the pilot valve (terminal 6) energized. De-
energizing the input (terminal 21) will force the unit through MTFI back into the AUTO
position.
5.
FRCD ON
– The purpose of FRCD ON (forced on) is to provide an input that can be controlled
by a smart lead/lag controller and if it is determined the lead boiler needs assistance to maintain
load demand, the lag boiler can then be forced into service.
a.
Burner turn on
With FRCD ON input inactive, the boiler will turn on if the control variable is below the
cut in
value.
With FRCD ON input active, the boiler will turn on if the control variable is below the
cut out
value.
b.
Burner turn off
The boiler will shut down if the control variable is above the
cut out
value.
If the boiler has been firing due to an active FRCD ON, and if the FRCD ON state is
changed to inactive, shut down will occur if the control variable is above the
cut in
value.
When LAG2 is set as FRCD ON, LAG 2 STRT DLY is used as a delay from when FRCD ON goes
active (terminal 21) to when the command to start the burner is actually given.
If the burner is firing and FRCD ON input is made inactive and the firing rate is above 25%, shut
down occur after the assured low fire cut off delay.
SEQUENCE OF OPERATION - STANDBY WATER
When the BurnerLogix is controlling a steam boiler, the water temperature sensor connected to the AUX1 input can be
programmed to operate in a:
1.
Standby Lag Mode
to monitor the boiler water of a steam boiler operating as the Lag boiler in
a Lead/Lag setup and cycle the boiler “on” to maintain the boiler water at a “Standby” tempera-
ture so the boiler is ready and available to come online and deliver steam to support the Lead
boiler.
2.
Standby Thermal Shock Protection Mode
to monitor the boiler water of a steam boiler and
slowly increase the burner firing rate on a cold start to limit mechanical stress based on the
boiler water temperature instead of steam pressure. The first step is to install a water tempera-
The user shall contact the burner manufacturer to determine if the pilot assembly is rated
for intermittent operation.
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Содержание BurnerLogiX BLL510
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