Siemens RWF55.51A9 User Manual

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Building Technologies Division User Manual RWF55... CC1U7867en
Infrastructure & Cities Sector 1 Introduction 05.11.2013
1.3 Description
The RWF55 is used primarily for the control of temperature or pressure in oil- or gas-
fired heating plants. Depending on the setting, it is employed as a compact 3-position
controller 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 8.4 Controller Cntr.
The controllers feature two 4-digit 7-segment displays for the actual value (red) and the
setpoint (green).
The RWF55 has a 3-position output consisting of 2 relays to open or close a controlling
element.
There is also an analog output and a multifunctional relay (K6), which can be used to
set 12 different switching functions.
The controllers feature an RS-485 interface Modbus slave as standard.
Additionally, the RWF55.6 features a Profibus DP interface.
In modulating mode, the RWF55 operates as a PID controller. In 2-stage mode, the
RWF55 provides control based on the set switching threshold.
You have the option of specifying the setpoint of the RWF55 on the controller or
externally via an interface.
The user uses it for control the temperature or pressure of a heating boiler or cooling
system.
It is possible to adjust the minimum and maximum setpoint limits.
2 binary inputs are used to execute functions such as setpoint changeover, setpoint
shifting or operating mode changeover.
Standard feature is a self-setting function used to determine the PID control
parameters.
The controller insert measures 48 x 96 x 122 mm and is especially suited for installation
in control panels. All electrical connections are made via screw terminals at the rear of
the unit.
Use in heating plants
Cooling controller
RWF55
Interface
Option
Control
Mounting

Siemens RWF55.51A9 Specifications

General

Brand	Siemens
Model	RWF55.51A9
Category	Controller
Language	English