3003237-2019-03-28.fm GB - Product information - MPT DUCT
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1.1.1 MPTDUCT bus line connection
Modbus,
termination
If the MPTDUCT is the first or last unit fitted to the BUS, set DIP-switch no. 8 on the COM
Selector to ON, which connects a 120 Ω terminating resistor. The drawing below shows
that the first and last unit on the BUS must be terminated, irrespective of which unit is
outermost.
1.2.1 Position dependent upon control method
The control method is set in the HMI panel. The type of air control methods that the
MPT DUCT must use and the values that have to be set, are described in the EXact
basic instructions
Alarm If control methods 3, 4, 5, 6 or 7 are selected on the HMI control panel, and the MPT
DUCT is not fitted or is not functioning, the HMI panel will display an error message.
1.2.2 Positioning the measuring probe
Position measurement probe (A) in the duct system so
as to avoid turbulence, typically 3-5 times the pipe
diameter from the unit, valves, bends, etc. In VAV sys-
tems, it is recommended that the measurement probe
be located at the two thirds point from the unit,
depending on zone division.
.There must be a seal between the measuring probe
plate and duct
1.2 Positioning the pressure transmitter (MPTDUCT)
If then
control method 3 or 5 is selected the measuring probe must be positioned in the extract air
duct
control method 4 or 6 is selected The measuring probe must be positioned in the supply air
duct
control method 7 is selected A measuring probe must be positioned in both the extract
and supply air ducts
control method 3,4,5,6 or 7 is
selected
the EXact control system automatically detects the MPT
sensors
