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System temperature probes
The BRAHMA system type TC340 is provided with several inputs
to control different temperature probes used for both temperature
adjustment and safety related functions. The characteristics and
functions of each probe are described in detail below.
-
Heating circuit probe (SR)
The heating circuit probe has the purpose to measure the heat
exchanger temperature and is mainly used in the FAN heating
function (see description in “OPERATION” section).
This probe can be of three types:
1) with double NTC sensor (standard version): in this case the
probe has a double function, as it enables to avoid mounting a
safety limit thermostat. This probe will therefore be used for
both temperature adjustment and safety functions (e.g. safety
shutdown due to system overtemperature).
To this purpose, a BRAHMA temperature probe type ST16 is
required.
J10
BRAHMA
type
ST16
BROWN
BLACK
BLUE
Fig. 1 – Connection of a double NTC probe
2) with single NTC sensor with contact safety thermostat (opt. T):
in this case the probe is provided with temperature adjustment
functions only, and any system overtemperature will have to be
controlled by a contact safety limit thermostat.
To this purpose, a BRAHMA temperature probe type ST08 is
required.
J10
BRAHMA
type
ST08
Safety limit
thermostat
Fig. 2 - Connection of a single NTC probe
3) with single NTC sensor without contact safety thermostat (opt.
NT): in this case the probe is provided with temperature
adjustment functions only, and any system overtemperature will
have to be controlled by an external safety device.
To this purpose, a BRAHMA temperature probe type ST08 is
required.
-
Room temperature probe (SA)
This (optional) probe can be used when the remote temperature
adjuster (BRAHMA chronothermostat type ENCRONO GA1) is not
directly mounted in the room requiring temperature adjustment, or
when this temperature adjustment should be related to the external
environment temperature. For further details about the functions of
this probe, please see the
"OPERATION" section.
To this purpose, a BRAHMA temperature probe type ST07 (for
local room temperature detection) or type SSE (for outside
temperature detection) is required.
Fire damper (STF)
This input (option S) enables to check the status of the fire damper
contact: in case this contact is open (anomaly condition), the
ignition cycle is interrupted and the device goes to stand-by
position signalling the failure through a LED. The behaviour of the
device in case the fire damper contact is open can be customized
upon request.
Overall dimensions
Fig. 3 shows the overall dimensions of this type of control units. All
dimensions are expressed in millimetres.
Fig. 3 – Overall dimensions
INSTALLATION DIRECTIONS
−
Respect the applicable national and European standards
regarding electrical safety (e.g. EN 60335-1/ EN 50165),
bearing in mind that ignition and flame control systems are
safety devices: the manufacturer's responsibility and guarantee
are invalidated in case of Customer's tampering with the
product;
−
before the first start-up, make sure that the loads are well
connected to avoid any dangerous situation or failure in the
appliance. Particular attention should be paid to earth
connections: make sure that all loads (fans, gas solenoid
valves, ignition transformer, …) are connected to the appliance
safety earth, using for example the connector on board;
−
the system is designed to stay in running status for less than
24h (system for non-permanent operation). Reaching this limit
causes a regulation shutdown to enable the unit to check its
own efficiency;
−
connect and disconnect the control unit only after switching off
the power supply;
−
the unit can be mounted in any position;
−
avoid exposure to dripping water;
−
a ventilated installation environment and a suitably low
temperature ensure the longest life of the control system;
−
before installing or replacing the unit, make sure that the type,
code and times are correct;
−
the appliance in which the control systems are installed should
provide adequate protection against the risk of electric shock
(at least IP20);
−
keep signal cables and power cables as far from each other as
possible;
−
use heat resistant detection cables and electrodes, and make
sure that they are well insulated to the ground and protected
from possible moisture or water in general;
−
keep the ignition cable as short and straight as possible and
place it far from other conductors to reduce the emission of
electromagnetic interference (max. length <2m and insulation
voltage >25kV).
71
65
67,5
Ø4
145
136
145
60
80,1
40
TWO-COLOUR
LED
RESET
P/BUTTON
