Siemens RDG400 - Manual (Page 24)

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Siemens RDG100…/RDG110…/RDG140.../RDG160… Basic Documentation CE1P3182en
Building Technologies Functions 28 May 2009
4.8.2 Control output for electrical heater, radiator and heating /
cooling coil
The valve receives an OPEN/ON command via control output Y1
1. When the acquired room temperature is below “setpoint” (heating mode) or
above the setpoint (cooling mode)
2. When the control outputs have been inactive for more than the “Minimum output
off-time” (factory setting 1 minute, adjustable via parameter P48).
OFF command for valve output:
1. When the acquired room temperature is above the setpoint (heating mode) or
below the setpoint (cooling mode).
2. When the valve has been active for more than the “Minimum output on-time”
(factory setting 1 minute, adjustable via parameter P49).
The electrical heater receives an ON command via the auxiliary heating control
output (Y1):
1. When the acquired room temperature is below “setpoint for electric heater”.
2. When the electrical heater has been switched off for at least 1 minute.
The OFF command for the electrical heater is output:
1. When the acquired room temperature is above the setpoint (electric heater).
2. When the electrical heater has been switched on for at least 1 minute.
A safety thermostat (to prevent overheating) must be provided externally.
• The demand calculated by PI control from the current room temperature and
setpoint is provided via Y10 as a continuous DC 0 ... 10 V signal.
• The signal converter (SEM61.4) converts the DC 0 ... 10 V signal to AC 24 V
PDM pulses for the current valve
• The current valve (SEA45.1) supplies the el. heater with AC 50 … 660 V pulsed
current.
Y E
DC 0 ... 10 V
Y1 G
L
N
Y1 L
Q
5.7 kW
max.
N1 U1
FF
F...
Y1
K...
G0
G
G
31
81
D
2
1
G
G0
Y PWM
AC 24 V
N1 RDG400
U1
Signal converter SEM61.4 (see data sheet N5102)
Y1 Current valve SEA45.1 (see data sheet N4937)
K… Safety "chain", e.g. safety thermostat and high-temperature cut-out
FF
Very fast-acting fuse
F… Overcurrent trip
ON/OFF control signal
(2-position)
Electrical heater
control signal
(2-position)
Caution
DC 0 ... 10 V
for el. heaters