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BACnet MS/TP
BACnet Master Slave/TokenPassing (MS/TP) is used for
communicating BACnet over a sub--network of
BACnet--only controllers. This is the default Carrier
communications protocol. Each RTU--MPm odule acts as
an MS/TP Master. The speed of an MS/TP networkcan
range from 9600 to 76.8K baud. Physical Addresses can
be set from 01 to 99.
Modbus
The RTU--MP module can speak the Modicon Modbus
RTU Protocol as described in the Modicon Modbus
Protocol Reference Guide, PI--MBUS--300 Rev. J. The
speed of a Modbus network can range from 9600 to 76.8K
baud. Physical Addresses can be set from 01 to 99.
JohnsonN2
N2 is not a standard protocol, but one that was created by
Johnson Controls, Inc. that has been made open and
available to the public. The speed of N2 network is
limited to only 9600 baud. Physical Addressescan be set
from 01 to 99.
LonWorks
LonWorks is an open protocol that requires the use of
Echelon’s Neuron microprocessor to encode and decode
the LonWorks packets. In order to reduce the cost of
adding that hardware on every module, a separate
LonWorks Option Card (LON--OC) was designed to
connect to the RTU--MP.
This accessorycard is needed for LonWorks and has to be
ordered and connected using the ribbon cable to plug J15.
The RTU--MP’s baud rate must be set to 38.4k to
communicate with the LON--OC. The address switches
(SW1 & SW2) are not used with LonWorks.
Local Access
BACview6Handheld
The BACview6is a keypad/display interface used to
connect to the RTU--MPto access the control information,
read sensor values, and test the RTU, see Fig. 68. This is
an accessory interface that does not come with the MP
controller and can only be used at the unit. Connect the
BACview6to the RTU--MP’sJ12 local access port. There
are 2 password protected levelsin the display (User and
Admin). The user password is defaulted to 0000 but can
be chan ged. The Adm in password i s1111 a nd cannot be
changed. There is a 10 minute auto logout if a screen is
left idle. See Form 48--50H--T--2T, Appendix A for
navigation and screen content.
VirtualBACview
Virtual BACview is a freeware computer program that
functions as the BACview6Handheld. The USB Link
interface (USB--L) is required to connect a computer to
the RTU--MP board. The link cable connects a USB port
to the J12 local access port. This program functions and
operates identical to the handheld.
RTU--MP Troubleshooting
Communication LEDs
The LEDs indicate if the controller is speaking to the
devices on the network. The LEDs should reflect
communication traffic based on the baud rate set. The
higher the baud rate the more solid the LEDs will appear.
C07170
Fig. 68 --BACview6Handheld Connect ions
48TC