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Siemens Building Technologies
Basic Documentation RVP540 / RVP550
CE1P2488en
HVAC Products
Description of the EXP settings
18.10.2002
With 2-position control, heat is produced at certain intervals . The period of time during
which heat is generated is dependent upon the mass to be heated up (boiler mass plus
water content), the flow rate and the burner's output.
°C
23
92
Z
31
ON
OFF
w
•
Setpoint for switching on
If the boiler temperature (TKx) falls by more than half the switching differential below
the currently valid boiler temperature setpoint (TKw), the burner will be switched on
•
Setpoint for switching off
If the boiler temperature (TKx) exceeds by more than half the switching differential
the currently valid boiler temperature setpoint (TKw), the burner will be switched off
The time switching off occurs can be delayed by the minimum burner running time.
Also refer to setting 253
EXP
.
TKw+SDK½
0
1
BR
23
71
D0
1
°C
TKw
TKw-SDK
½
TKx
t
40°C
BR Burner
TKx
Actual value of boiler temperature
TKw
Boiler temperature setpoint
SDK Switching
differential
t Time
The second burner stage is switched on and off based on the settings made on the
operating lines:
•
release limit (integral) of burner stage 2
Operating line 254
EXP
:
•
reset limit (integral) of burner stage 2
Operating line 255
EXP
:
Boiler temperature
control
Switching differential
Single-stage burner
Note
2-stage burner