Selection Process; Hydraulic Manifolds; Mixed Circuits; Analog Input - Rehau NEA SMART 2.0 Service Manual

5.3

Selection Process

5.3.4.1 Hydraulic Manifolds

Based on the number of rooms served and the associated pipe loops
for each manifold, the NEA SMART 2.0 components can be selected
using selection table 5-1.
Number of rooms
(identical to Room units)
Number of pipe loops (identi-
cal to number of actuators)
Tab. 5-1 Selection matrix
Any room (unit) can be assigned to any number of hydraulic circuits /
actuators on one NEA SMART 2.0 Base or R-Module. That means that
one NEA SMART 2.0 Room unit could be assigned to 20 hydraulic
circuits / actuators. However, in such a case the use of a zone valve,
that controls the manifold as one, should considered instead. Only one
pipe loop/actuator can ever be assigned to one room unit.
Sometimes there can be two hydraulic manifolds serving the same room.
A meeting room in an office building may have an underfloor heating
system as well as a chilled ceiling installed, each supplied by its own
manifold. Placing the NEA SMART Base station next to the underfloor
heating manifold and the R-module next to the one for the ceiling system
would all the control of both systems with a single room unit.
Special attention is necessary, when within one room more than
system is installed and if the systems are used for heating and/ or
cooling. For example a room with
underfloor heating only,
wall heating and cooling
ceiling cooling only.
In this case, there would only be one room unit needed, but at least
3 different outputs for actuators are needed (one for each system).
An extra NEA SMART 2.0 Transformer is recommended next to the
NEA SMART 2.0 R-Module.
The NEA SMART 2.0 Base and R-Module should be placed close to
each hydraulic manifold because the actuators for each pipe loop
have a limited cable length.
This setup is repeated for every manifold. As a result, the overall
number of NEA SMART 2.0 Bases and R-Modules are defined.
1 ... 8 9 ...
1 ... 12 13 ...
NEA SMART NEA SMART
+
2.0 Base 2.0 R-Module
NEA SMART
2.0 Transfor-
mer
5.3.1

Mixed circuits

NEA SMART 2.0 can control mixed circuits only for heating, cooling,
heating and cooling or any combination of these. Every mixed circuit
will need one NEA SMART 2.0 U-Module. The total number of three
mixed circuits must not be exceeded.
The NEA SMART 2.0 U-Module should be placed close to the mixing
valve to keep wiring to a minimum.
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5.3.2 Dehumidifiers
20
There are two possibilities to control dehumidifiers:
- Make use of the digital outputs of a NEA SMART 2.0 Base and
R-Module (maximum 1 dehumidifiers can be wired to one Base)
- Make use on a NEA SMART 2.0 U-Module (maximum 2 dehumidi-
fiers can wired to one U-Module)
The decision to use the NEA SMART 2.0 Base or the NEA SMART 2.0
U-Module depends on the following:
- Number of digital outputs available at the NEA SMART 2.0 Base.
This is important to know because some digital outputs may be
used for other functions, such as change over heating / cooling or
boiler demand signal
- Distance between the dehumidifiers and the NEA SMART 2.0 Base
and necessary wiring
A maximum number of nine dehumidifiers must not be exceeded.
5.3.3

Analog Input

Analog inputs can be used to receive information about temperatures.
There are two ways to receive analog inputs, either via the NEA
SMART 2.0 Room unit or via the NEA SMART 2.0 U-Module when
being used as mixed circuit control.
NEA SMART 2.0 Room Unit
The NEA SMART 2.0 Remote sensor can be connected to any NEA
SMART 2.0 Room unit and its function selected during system setup.
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