Downstream Devices (I/O) - Honeywell MPA2 Installation Manual

Installing the MPA2 Panels
Installation

3.6 Downstream Devices (I/O)

UL has not evaluated the compatibility of downstream I/O devices
Note:
with the MPA2 panel.
In some applications, the number of system inputs or outputs exceeds the
number that is standard on the MPA2 panel. The solution is to add a
combination of NX4IN and NX4OUT downstream I/O devices external to
the MPA2 enclosure on a dedicated RS-485 Interface bus. A maximum of
two NX4IN and a maximum of four NX4OUT for a total of six Downstream
I/O Devices can be added to the downstream bus.
A NX4IN module has 32 supervised, four-state inputs that are limited to
2.2K ohms resistance. The NX4OUT has two supervised inputs and 16
SPDT relay outputs; each input is limited to 2.2K ohms resistance. Refer to
the individual installation manuals for I/O wiring details.
The Interface bus is wired into the MPA2 using standard CAT 6E/7 (S)/FTP/
UTP cable with RJ45 plug (J16) on the board. The Interface bus has a
fixed baud rate and communicates to the downstream I/O devices using a
polling technique.
Each downstream I/O device needs to have a unique address for proper
communication. Each one also has some configuration jumpers that need
to be positioned correctly. The following table lists the DIP switch and
jumper settings for the NX4IN and NX4OUT downstream devices.
If the MPA2 controller is physically terminating one end of the RS-485
bus line as shown in
Downstream I/O is not supported. Please contact Technical support
Note:
for more details.
38 www.honeywell.com
Figure 10 on page 40, set S1 positions 5 & 6 to ON.