Communication Bus - Buderus EM10 Manual Del Usuario

Module EM10

Communication bus

Connect the EMS connection (fig. 2, pos. 6) of the EM10
with a 2-core cable to the RC- (or
boiler (possibly parallel to the thermostat).
Caution: This connection is polarity sensitive. The total
length of the EMS bus cable may be no more than 100 m.
Malfunction signal
The malfunction signal is given when:
– a locking malfunction occurs in the boiler,
– the system pressure is too low or
– the communication with the boiler has been interrupted
for at least 5 minutes. See wiring diagram on page 47.
The EM10 generates two malfunction signals:
a) The AS 24 V connection (fig. 2, pos. 4), this is a
potential-free switching contact for low voltage signals of
up to 24 V. This malfunction signal can for example, be
evaluated by a building management system.
AS 24 V no malfunction
1 and 2 interrupted
2 and 3 closed
b) The AS 230 V connection (fig. 2, pos. 3), this can for
example operate a horn or warning light. In case of a
malfunction, there will be 230 VAC on this connection.
External control signal 0-10 V
The EM10 can be used as an interface between the boiler
and, for example, a building management system.
With the 0-10 V DC signal (fig. 2, pos. 5), the flow tempera-
ture or the power of the boiler can be controlled (fig. 3).
a) Flow temperature-based control
The EM10 transfers the 0-10 V signal to a flow
temperature-setpoint. This is a linear ratio, see table 1.
Input
voltage
0 V - 0.5 V
0.6 V
5.0 V
10.0 V
table 1 Flow temperature-based control
Changes due to technical improvements reserved
Module EM10 • 01/2008
-) connection on the
malfunction
closed
interrupted
Flow temperature
Setpoint (boiler)
0
± 15° C
± 50° C
± 90° C
Netz module
1
fig. 2
pos. 1: 230 V mains supply
pos. 2: 230 V connection for a 2nd module
pos. 3: Alarm output 230 V
pos. 4: Alarm output 24 V
pos. 5: Control signal 0-10 V
pos. 6: Input EMS bus
pos. 7: Output EMS bus
Status
Boiler
off
on
on
fig. 3
on/maximum
AS 24V
N L
1 2 3
Netz module AS (230V)
2 3 4
Connections
External control voltage (V)
0 – 10 V diagram
English
U EMS EMS
2 1 3 1 2 1 2
5 6 7
13