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NTC PROTECTION
X9 6- pin
Molex-Minifit (White)
Series 5566
-1
24V DC
-2
Gas pressure switch
-3
Air pressure switch
-4
Blocking input
-5
Reset
-6
Security thermostat
X10 4- pin
Molex Minifit (Blue)
Series 5566
-1
I2C
-2
I2C
-3
I2C, earth
-4
Not occupied
X11 4- pin
Molex Minifit (White)
Series 5566
-1
RS232, RX
-2
RS232, TX
-3
RS232, 5V DC
-4
RS232, earth
X12 10- pin (SIT-interface for gas-mixture control)
Transformer (Tr1)
HS- Ignition/Ionisation
10. NTC Protection
Cause
Limits
Reaction
Boiler sensor 1 / Boiler sensor 2:
Sensor short circuit
125 °C
Lock-out
Sensor not connected
-25 °C
Lock-out
Lock-out temperature
110 °C
Lock-out
Maximum temperature difference between sensor 1 and sensor 2
10 °C
Lock-out
Blocking temperature
Value dependent on
boiler type
Blocking
Maximum temperature rise with low flow temperature
1)
1 °C/sec
Min. capacity
Maximum temperature rise with high flow temperature
2)
0.5 °C/sec
Min. capacity
1)
‟Low” flow temperature 60 °C
2)
‟High” flow temperature 80 °C
Flue gas sensor (only available from UltraGas
®
):
Flue gas sensor short-circuit
125 °C
Lock-out
Flue gas sensor interruption
-25 °C
Lock-out
Flue gas temperature lock-out
110 °C
Lock-out
Flue gas temperature blocking
100 °C
Blocking
