© 2016
CONTRIVE • B14
88|
QBK
.EN
0219
14
www.contrive.it
DUAL STAGE BURNER
Turn ON/OFF the burner by means of thermostat input at terminal 16 or through remote fieldbus command.
Depending on configuration, the pilot burner could be:
INTERRUPTED - extinguished at the end of the second safety time.
INTERMITTENT - shut off simultaneously with the main flame.
Flame detection options:
A single flame detector monitors both the pilot and main burner.
PURSUANT TO EN 746
-2: A SINGLE COMMON FLAME SAFEGUARD IS AL
LOWED FOR BURNERS THAT GUARANTEE STABLE COMBUSTION
THROUGHOUT THE RANGE OF REGULATION AND ARE ON THE SAME AIR/GAS RATIO CONTROL SYSTEM, ARRANGED ADJACENT AND IN
SUCH WAY THAT, IF ONE OF THEM IS EXTINGUISHED, IT IS RE-
IGNITED QUICKLY AND SMOOTHLY BY THE FLAME FROM THE NEXT BURN
ER.
Pilot and main flame detected by two independent sensors wired at same input.
PURSUANT TO EN 746
-2: WHEN TWO INDEPENDENT SENSORS SHARES THE SAME FLAME AMPLIFIER INPUT, THE MAIN FLAME SENSOR
SHALL BE SO
POSITIONED THAT IT CANNOT IN ANY CIRCUMSTANCES DETECT THE PILOT FLAME
Both UV detector or ionization rod can be used for pilot and main burner.
Once the pilot burner has started up, the main burner can be controlled by means of thermostat input at terminal 17
or through fieldbus command.
Turning off the main burner when the pilot burner is operating in INTERRUPTED mode will lead to a new burner
ignition trial (1
st
safety time) including spark generation.
The air output operation is configurable during the whole cycle, providing also cooling and purging processes.
For modulating burners, the butterfly valve must be managed by external logic.
See SINGLE STAGE BURNER
description for process input description.
EXTERNAL LIMITS
RESET INPUT
LOW AIR PRESSURE SWITCH
AIR CONTROL INPUT
AIR VALVE
ON/OFF THERMOSTAT INPUT
PILOT GAS VALVE
MAIN THERMOSTAT INPUT
MAIN GAS VALVE
BURNER ON
UV SENSOR (MAIN)
BURNER LOCKOUT
SINGLE ROD CIRCUIT (PILOT)
MAKE JUMPER A1
-A2 WHEN
LOW AIR PRESSURE SWITCH
IS NOT INSTALLED
