Description - Siemens RWF50.3 User Manual

Use in heating plants
Cooling controller
RWF50...
Control
Mounting
Building Technologies Division
Infrastructure & Cities Sector

1.3 Description

The RWF50... is used primarily for the control of temperature or pressure in oil- or gas-
fired heating plants. Depending on the model, it is employed as a compact 3-position
controller without feedback of angular positioning or as a modulating controller with an
analog output. An external switch is provided to convert it to a 2-position controller for
controlling 2-stage burners. The built-in thermostat function switches the burner on and
off.
The controller's operating mode can be changed from heating to cooling, or vice versa.

Reference!
See chapter 8.2 Controller Cntr.
The controllers feature two 4-digit 7-segment displays for the actual value (red) and the
setpoint (green).
The RWF50.2 has a 3-position output consisting of 2 relays to open or close a
controlling element.
The RWF50.3 has an analog output.
In modulating mode, the RWF50... operates as a PID controller. In 2-stage mode, the
RWF50... provides control based on the set switching threshold. Using the binary input,
a change to a second setpoint can be made or the setpoint can be shifted. Standard
feature is a self-setting function used to determine the PID control parameters.
The controller insert measures 48 x 48 x 104 mm and is especially suited for installation
in control panels. All electrical connections are made via screw terminals at the rear of
the unit.
User Manual RWF50...
1 Introduction
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CC1U7866en
25.07.2014