AERMEC WMT21 Manual De Instrucciones página 49

thermostats in the same building (centralised Heating/Cooling function).
RS connector, or alternatively terminals 14 and 15, can be used to connect
an external room temperature sensor. Change configuration to select
external or internal sensor use.
Terminals 13 and 14 is an input to connect different types of sensors
for special functions: connect a delivery temperature sensor for the
"changeover" and/or "cut-off thermostat" function, or connect a bimetal
thermostat with "cut-off thermostat" function. Change configuration to
select which type of sensor to use (P08).
The device is suitable to control both an electronic fan motor (EC motor)
and a three speeds fan motor. Use parameter P05 to decide whether
to use the 0-10V proportional output for an EC motor or the three relay
outputs for a three speeds motor. If the proportional output is used, the
0-10V signal will be available on terminal 11, while the reference ground
on terminal 12. Connect the EC motor as shown in Fig. 13a. If the three
relay outputs for a three speeds motor are used, the outputs are available
on terminals 6, 7 and 8, while terminal 5 is the relays common. Connect
the three speeds motor as shown in Fig. 13b.
The fan motor outputs, terminals 5 to 8, are voltage free and insulated
with reinforced insulation towards the other circuits of the thermostat.
Therefore, a thermostat can be supplied with SELV low voltage (24V~),
while controlling a high voltage fan (230V~), as shown in Fig. 10.
In this case, 24V~ SELV and 230V~ cables must be separated in
accordance with current standards.
In particular, it is necessary to secure the two groups of cables with cable ties
separating the SELV wires from the others. This is required to avoid that the
insulation to SELV is reduced in the event of a wire accidentally disconnects.
a
WARNING
- Installation and electrical wirings of this appliance must be
made by qualified technicians and in compliance with the current
standards.
The device can control one or two 0..10V proportional actuators or one
or two ON/OFF actuators. The outputs for the ON/OFF actuators are only
available when there is a proportional motor, i.e. when the relay outputs
are not used to control the three speeds motor.
The heating 0..10V proportional output is available on terminal 9, while
the cooling output on terminal 10, Fig.12d. For two-pipes systems, a single
valve is used both for heating and cooling and in this case the control signal
will be the heating one available on terminal 9, Fig.12b.
For all 0..10V signals (valves and fan), the reference ground is available on
terminal 12. Please note that the ground is electrically connected to the
power terminal N (Neutral).
To connect 24V actuators, follow diagrams in Fig.9 and 10, while
follow Fig. 8 for 230V actuators. Usually 0..10V actuators only have 3
connection wires, as the ground of the input signal is internally connected
to one of the two power-supply wires (Neutral). In this case there is no
need to connect terminal 12 (output signal ground), as the actuator uses
the Neutral power terminal as ground. Make sure the latter is connected
to terminal N.
When using ON/OFF valves, the heating output is available on terminal 6
and the cooling output on terminal 7 Fig. 12c.
In the case of two-pipes systems, only one valve needs to be connected to
the heating output. Connect it as shown in Fig. 12a.
It is possible to manage systems with two different kinds of valves for
heating and cooling, for instance ON/OFF heating output and 0..10V
proportional cooling output.
If the system has an electric heater for integrations or to replace the
heating valve, connect according to diagrams in Fig. 12e or Fig. 12f.
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