Siemens RDG400 Position control, Signal, Position actuator, Parameter P44 Y1 and Y2, PWM control

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3-position control

Output Y1 provides the OPEN command, and Y2 the CLOSE command to the 3-

signal

position actuator.

 

The factory setting for the actuator runtime is 150 seconds. It can be adjusted via

 

parameter P44 (Y1 and Y2).

 

The parameter is only visible if 3-point is selected via DIP switch 5.

Synchronization

1. When the thermostat gets powered up, a closing command for the actuator

 

runtime + 150 % is provided to ensure that the actuator fully closes and

 

synchronizes to the control algorithm.

 

2. When the thermostat calculates the positions "fully close" or "fully open", the

 

actuator runtime is extended + 150 % to ensure the right actuator position

 

synchronized to the control algorithm.

 

3. After the actuator reaches the position calculated by the thermostat, a waiting

 

time of 30 seconds is applied to stabilize the outputs.

PWM control

The demand calculated by PI control from the current room temperature and set-

 

point is provided via Y1 to the valve actuator as a PWM signal (Pulse width

 

modulation) for thermic actuators. The output is switched on for a period proportio-

 

nal to the heat/cool demand and then switched off for the rest of the PWM interval.

 

The interval is 150 sec (factory setting). It can be adjusted via parameters P44

 

(Y1). The parameters are only visible if 2-point is selected via DIP switch 5.

PWM for thermic

For thermic valve actuators, set the running time to 240 sec.

valve actuators

Never apply PWM to a motoric actuator.

Note!

 

It is not possible to ensure exact parallel running of more than one thermic valve

 

actuator. If several fan coils are driven by the same thermostat, preference

 

should be given to motoric actuators.

PWM for el. heaters

For electric heaters, set the running time to 90 sec.

 

In order to avoid burn-off of mechanical contacts by frequent switching, use a

 

current valve instead of a relay or contactor.

 

 

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Siemens

RDG100, RDG100T, RDG110, RDG140, RDG160 Basic Documentation

CE1P3182en

Building Technologies

Functions

28 May 2009

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Contents Edition CE1P3182en 28 May Building TechnologiesTable of contents Revision history About this documentReference documents Before you startDocument use / request to the reader Features Types and featuresSummary Brief descriptionEquipment combinations Use AccessoriesOrdering SSA81 SSP81… SSB81 SSD81 SQS85…Functions Temperature controlGeneral note Described in sectionOperating modes Comfort mode Energy Saving Protection modeSetpoints Setpoints and sequence Comfort mode Energy Saving Protection mode ApplicationSingle duct With min/max Limitation Single duct With Electrical HeaterHeating mode Cooling mode Single duct Comfort mode Energy Saving mode ApplicationProtection mode Heating mode Cooling mode With heating Cooling coilApplications overview Additional features External / return air Temperature sensorFloor heating Limitation functionButton lock Sec after the last adjustmentLocked or unlocked by pressing the right button for 3 sec Comf Extension Prot Absence Not available EcoParameter P01 = Sequence Mode Sequences overview setting via parameter P01Control sequences Applications and sequencesSingle-duct heating / cooling coil Function of the control outputs is set via DIP switches 4DIP Y10 = … 10 10 … 0 V inverted PositionSingle duct Setting the sequence and the control outputsHeating or cooling Modulating control 3-position, PWM or DC 0 … 10Sequences Single duct with electrical heaterModulating electrical heater Modulating radiator / floor heating Single duct with radiator or floor heatingControl sequence Single duct with heating / cooling coilModulating heating / cooling coil Control output for air flow Control outputsSynchronization ON/OFF control signal Position control SignalPosition actuator Parameter P44 Y1 and Y2AI/DI Multifunctional input, Digital inputDIP switches Handling of faultsTemperature out RangeControl parameters Parameter settingChange the parameters as follows Service level Parameters Service levelExpert level Parameters Expert level, diagnostics & testDiagnostics & test Wiring Mounting and installationHandling MountingLayout OperationButton operation User actionLCD display DisposalConnection terminals EngineeringConnection diagrams Mechanical design DimensionsGeneral Power supply Outputs Inputs Operational data Technical dataPage Automatic heating/cooling changeover Index