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Siemens
RDG400 Basic Documentation
CE1P3182en
Building Technologies
2015-05-20
4.8.2 Control output for electric heater, radiator and
heating/cooling coil
The valve receives an
ON
command via control output Y1 when…
1.
the acquired room temperature is below the setpoint (heating mode) or above
the setpoint (cooling mode),
2.
the control outputs have been inactive for more than the "Minimum output off-
time" (factory setting 1 minute, adjustable via parameter P48).
The
OFF
command for valve output when…
1.
the acquired room temperature is above the setpoint (heating mode) or below
the setpoint (cooling mode),
2.
the valve has been active for more than the "Minimum output on-time" (factory
setting 1 minute, adjustable via parameter P49).
The electric heater receives an
ON
command via the auxiliary heating control
output (Y1) when…
1.
the acquired room temperature is below "setpoint for electric heater",
2.
the electric heater has been switched off for at least 1 minute.
The
OFF
command for the electric heater is output when…
1.
the acquired room temperature is above the setpoint (electric heater),
2.
the electric 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 modulating 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 electric 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
3
1
8
1
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 loop (e.g. safety thermostat and high-temperature cutout)
FF
Very
fast-acting
fuse
F… Overcurrent
trip
On/Off control signal
(2-position)
Electric heater control
signal
(2-position)
Caution
DC 0...10 V
for electric heaters
