Hi-T2
Centralised controller
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The “Hi-T2” remote control panel allows you to view the working parameters of each individual water terminal unit and those of
each individual zone.
It is possible to manage up to 80 water terminal units which can be divided into 9 thermal zones. Each water terminal unit, once it
receives the relative setting of the zone it belongs to, uses the proper temperature probe as a working probe.
When installing the RFC system with our I-32V5 chillers, it is possible to manage with a single Hi-T2 remote control panel up to 7
chillers/heat pumps in cascade and up to 80 terminal units divided into 9 thermal zones. The connection between the Hi-T2 remote
control panel, chillers and water terminal units is very simple: it requires a shielded twisted pair cable SSTP (e.g. CAT5) connected in
series.
Possible configurations:
•
1 chiller/heat pump without water terminal units connected
•
up to 7 chillers/heat pumps in cascade without water terminal units connected
•
1 chiller/heat pump with connected terminal units (up to 80 units)
•
up to 7 chillers/heat pumps with connected terminal units (up to 80 units)
The chillers/heat pumps which shall be connected in cascade do not require additional work probes to place in the total system
outlet pipe since the centralized system acquires the individual temperatures of each unit and controls the average flow
temperature. The advantage of a combined RFC system lies in the fact that the only interface for the user is the Hi-T2 touch-screen
remote control which is an easy and user-friendly interface for setting and monitoring the "water terminal units + chiller/heat
pumps" system. It is also possible to connect in cascade chillers/heat pumps of different output capacities; the Hi-T remote control
panel can determine the installed output. From the remote control display, you can also know the number of the operating water
terminal units respect to those installed and the number of active chillers in the network compared to the installed ones.
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CONNECTION NETWORK
The connection network is based on the RS-485 electrical standard and on the standard Modbus RTU protocol. The network consists
of a "master unit", “Hi-T2” remote control panel, and a variable number of "slaves". The chillers/heat pumps with addresses from 1
to 7 are considered as "slaves". The RFCs with addresses from 10 to 96 are "slaves" (actually up to a maximum of 80 fan coils can be
configured).
Here are some important notes for the network’s electrical connection:
1.
Use an adequate cable for RS-485 standard (twisted and shielded). It is also possible to use common CAT.5 UTP cables, but
the effect is to reduce the maximum network length in half.
2.
Connect the bus in a daisy-chain fashion (enter/exit type), as shown in the figure. It is considered bad practice to create
branches that connect devices with the main backbone of the bus, though they are allowed if they do not exceed 2m long.
3.
In the most classic installation, a "baudrate" of 9600bps is used; in this configuration the maximum network length is about
1000m.
4.
Connect 120Ω termination resistors at the beginning of the bus (Hi
-T) and at the end (last "slave"). The heater on Hi-T2 is
already present on the hardware; just bring the dip switch over the 3-4 connectors to the ON position. On the "slave" insert
a physical resistor between the 2 poles (R + / R- for the chillers, A/B for the RFC modules).
5.
Respect a minimum length of 1 meter between the devices in the bus.
6.
Do not connect the GNDR to earth
AUTO
