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RESETTING THE CONTROL UNIT
Non-volatile lockout (manual reset)
If the control unit goes to non-volatile lockout, to reset the system
press the reset push-button (mounted on board or on the BRAHMA
chronothermostat type ENCRONO GA1) till the lockout signal
switches off.
Volatile lockout (electrical reset)
In case of volatile lockout, the control unit can be reset by cutting
off and then restoring the power supply. It is not possible to reset
the system by switching off the heat demand device.
OPERATING CYCLE VARIATIONS
Followings are the available operating cycle variations of the
control units:
− Option 9 (“K”, “Knn”): lockout due to extraneous light
If extraneous light is detected at start-up or during the waiting/pre-
purge time, the control unit will proceed to lockout immediately
(option “K”) or with a delay (expressed in seconds) settable upon
request (option “Knn”).
− Option 10 (“Qnn”): insufficient or no air flow at start-up
If insufficient or no air flow is detected or the pre-heater thermostat
does not switch at start-up or during the waiting/pre-purge time, the
control unit will go to lockout within 3
÷
120 seconds (the time is
settable upon request).
− Option 11 (“R”): insufficient or no air flow in running status
In case of air failure in running status, the ignition and flame control
unit proceeds to immediate lockout.
− Option 12 ( “V”): flame failure in running status
In case of flame failure in running status, the control unit proceeds
to immediate lockout.
− Option 13 (“Pnn”, “PTnn”): post-purge time on EF burner motor
The control unit carries out a post-purge action on the EF
combustion motor fan (the time is settable upon request).
With option “Pnn”, post-purge is carried out regardless of the heat
demand status; with option “PTnn”, post-purge can be interrupted
by restoring the heat demand and having a new ignition cycle start.
− Option 14 (“Ynn”): recycling attempts
The control unit performs multiple recycling attempts in case of
burner ignition failure (the number of attempts is settable upon
request).
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!!
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IMPORTANT NOTE
The indication “nn” corresponds to the max. allowed number of recycling attempts
and is not therefore the total number of ignition cycles carried out in case of heat
demand switching on.
For example, a system with option Y2 can carry out a max. of 2 recycling attempts,
but the total number of ignition cycles starting from the heat demand switching on is
3 (1 ignition cycle + 2 recycling attempts).
− Option 15 (“Inn”): inter-waiting or inter-purge time
A waiting or pre-purge time (expressed in seconds) is performed
after a failed ignition attempt and before the next recycling attempt.
− Option 16 (“G”, "GP"): air pressure switch checking
Option "G", available in the devices type TC340A, enables the
control unit to start the ignition cycle without checking the air
pressure switch; option "GP", available in the devices type TC340P
and TC340P1, allows the air pressure switch checking during the
pre-purge stage and at start-up only.
− Option 17 (“Jnn”): pre-ignition time
The transformer is switched on at the end of the waiting/pre-purge
time and before the beginning of the safety time, for a time settable
upon request.
− Option 29 (“QS”): QuickStart function
This function enables to carry out a short pre-purge in case the
heat demand is restored before the end of a post-purge phase (for
this reason, this function can only be requested in case the PT
function is available), in order to perform the ignition as soon as
possible by exploiting the portion of post-purge already
accomplished.
To better understand this function, please refer to figure 9,
representing an example with a control unit having a pre-purge
time and a post-purge time of 10 seconds: if the heat demand (HR)
is restored, for example, 6 seconds after the beginning of the post-
purge, the device will carry out a pre-purge equal to 10 - 6 = 4
seconds, i.e. the difference between the nominal pre-purge time
and the performed post-purge time.
Fig. 9 – QuickStart function
SIGNALLING DURING OPERATION
The system can signal its operation status or the presence of any
anomalies by a two-colour LED. The following figure represents the
main standard displays of the unit, which can be modified upon
request.
Stand-by
Pre-purge
Ignition
Waiting time before running status (RP1)
Running status (RP2)
STF contact opening
General lockout
Lockout due to overtemperature
Extraneous light / SR probe failure
Fig. 10 – Main LED displays
In case the control unit is not installed in frontal position next to the
hot air generator panel, both the light signals and the reset signals
can be remoted by using, for example, a BRAHMA interface
module type 865. Otherwise, if requested, the SL2 outputs of the
J4 connector (see
"Wiring diagrams"
section) can be used to
manage any external auxiliary devices (e.g. a BRAHMA device
type 343).
COMMUNICATION INTERFACE
The BRAHMA system type TC340 can communicate with a
personal computer through RS-232 communication protocol. The
communication interface enables to:
-
check the operation status of the unit and carry out some
diagnostic functions to locate any anomalies or errors in the
system;
-
programme the “open" parameters of the unit (e.g. the motor
speed in different modulation stages, the switch-on delay time
and the post-purge time of the FAN blower, the T
ON
and T
OFF
intervention thresholds, …).
The serial interface of the system can be used by means of the
BRAHMA interface device type 810 and dedicated management
software.
