Acquisition Of Actual Values; General Remarks About Faults In The Measuring Circuits; Flow Or Boiler Temperature; Outside Temperature - Siemens RVP201 Basic Documentation

Types of sensors
Handling of faults
Types of sensors
Handling of faults
Types of sensors
Handling of faults
Siemens
Building Technologies
3.2

Acquisition of actual values

3.2.1

General remarks about faults in the measuring circuits

In the event of a faulty temperature sensor, the RVP201/211 always attempts to main-
tain the required comfort level in the best possible way, even if a certain amount of heat
is wasted.
In the case of serious faults that do not allow the RVP201/211 to ensure control, a fault
message will be generated. This is indicated on the controller front by the LED which
starts flashing when the current operating mode is overridden.
3.2.2

Flow or boiler temperature

Suitable are all temperature sensors that use a sensing element LG-Ni 1000
Clamp-on temperature sensor QAD22
Immersion temperature sensor QAE212...
Immersion temperature sensor QAP21.3 (complete with a ready connected cable)
If a fault occurs in the control sensor's measuring circuit (short-circuit or interruption), the
control switches itself off (mixing valve closes or burner off, heating circuit pump on).
In any case, a fault message will be delivered; the LED on the controller front flashes.
3.2.3

Outside temperature

The following types of outside sensors can be used:
QAC22 with a sensing element LG-Ni 1000
QAC32 with a sensing element NTC 575
The controller automatically identifies the type of sensor connected.
If a fault occurs in the outside sensor's measuring circuit, the control responds as fol-
lows:
Plants with a room temperature sensor:
The controller switches to pure room temperature control
Plants without a room temperature sensor:
The controller ensures control based on a fix outside temperature of 0 °C
A fault message is generated only when there is no actual value of the room tempera-
ture available. This is the case when no room unit is present or when the room temper-
ature measuring circuit is faulty. The LED on the controller front flashes.
3.2.4

Room temperature

The room temperature is acquired via a PPS (point-to-point interface). Only room units
that deliver suitable output signals can be connected to it.
The following types of room units can be used:
Room unit QAA50..
Room unit QAW70 (room temperature sensor QAW44 can be connected in parallel)
It is also possible to connect an external switch for changeover of the current operating
mode to the PPS interface (also refer to "4 Handling"). When the switch is closed, the
room temperature cannot be measured.
Short-circuits or interruptions at the terminals do not trigger fault messages since these
statuses have a defined meaning:
Interruption = no room unit connected
Short-circuit = an external switch, if present, is activated
Heating controllers RVP201 and RVP211
3 Technical design
at 0°C
at 20°C
at 0 °C:
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CE1P2464en
2017-07-21