Specifications

Ammonia Gas Monitor – Multi Zone
Instruction 3015-5113 19
Multiple AGMs
Multiple AGM-MZs With AGM-RD
NOTE 1: The last AGM-MZ or AGM-RD on either end of the network must have its
terminator in the “IN” position, and all other units must have their terminators in the
“OUT” position.
NOTE 2: The total length of the RS-485 cable cannot exceed 4500 feet. (Use instrument
cable 20 gage multi-strand shielded and twisted pair – similar or equal to Belden
cable #8762.)
RS-485 Connections Between AGM-MZs
NOTE: The terminators in the AGM-RD and AGM-MZ Unit 4 must be in the “IN” position.
The terminators in AGM-MZ units 1, 2 and 3 must be in the “OUT” position.
TERMINATOR TERMINATOR TERMINATOR TERMINATOR
“OUT” “OUT” “OUT” “IN”
Connecting to a Building Management System
The AGM-MZ may be connected to a Building Management System via the RS-485 connector. The node
address on each AGM-MZ may be set from “1” to “15” in order to identify itself to the Building Management
System. Note that Building Management Systems set to a “0” or “1” address both respond to messages from
the AGM-RD as address “1” therefore you should not have a unit set to “0” and another set to “1” on the same
network.
If the AGM-MZ network is connected directly to a Building Management System it may not
be connected to
the AGM-RD. However, the AGM-RD has two communication ports, an “upstream” port (labeled BMS) and a
“downstream” port (labeled TO MONITORS). A BMS node may be connected to the up stream AGM-RD port
while the downstream AGM-RD port talks to the AGM-MZs. In this case, the BMS is talking “through” the
AGM-RD to the AGM-MZs, but not physically on the AGM-MZ/AGM-RD network.
NOTE: If the AGM-MZ is not at the end of the line in a series connection, then the terminator on the AGM
must be set to “OUT.” Also, each end of the series must have the terminator set to “IN”.
Multiple AGM-MZs Connected to a Building Management System
TERMINATOR
“OUT”
TERMINATOR TERMINATOR TERMINATOR TERMINATOR
“IN” “OUT” “OUT” “IN”
AGM-RD
AGM-MZ
UNIT 2
NODE 2
AGM-MZ
UNIT 3
NODE 3
AGM-MZ
UNIT 4
NODE 4
AGM-MZ
NODE 1
AGM-MZ
NODE 2
AGM-MZ
NODE 3
AGM-MZ
NODE 4
BMS
TERMINATOR
“IN”
AGM-MZ
UNIT 1
NODE 1
RS-485