CLSS Gateway - Installation and Users’ Manual | P/N:LS10248-000HW-E | REV. F | FEB/11/2022 59
Analog Values and Trending Modbus Communications
7.21 Analog Values and Trending
Trending of analog values is supported on all of the panels/networks 4–20 mA modules.
The only limitation is that the gateway will only actively read analog values for up to 10
analog modules at a time. All the analog values on all the modules can be read as long as
a separate poll is sent for these points in groups of up to 10 points at a time, following the
rules outlined below. Refer to
"Analog Value Use Cases" for clarity on this issue.
• Accept a poll for up to any 10 analog (4–20 mA) points per gateway.
• Requests for more points than this are rejected with an exception code.
• If any of the points in the request are not 4–20 mA modules then the gateway rejects
the request with an exception code.
• The first poll for analog values is an initialization poll. This initialization poll informs the
gateway to start acquiring analog values for these points at 5 second intervals.
• Points are only polled on the NFN if the 4–20 mA module is in at least the first level of
alarm status. If the point is normal then the gateway returns a value of zero.
* Activate and Deactivate work only for output-controlled modules like
control and relay.
Different panels support different zone types. Refer to Table 7.8, “Zone
Command Availability by Panel” for information about zone types
supported.
Table 7.8: Zone Command Availability by Panel
General Zones Logic Zones
Trouble/Release
Zones
Panel Type
Enable/
Disable
Activate/
Deactivate
Enable/
Disable
Activate/
Deactivate
Enable/
Disable
Activate/
Deactivate
AFP-2800
Yes No No No No No
AFP-3030
Yes No No No No No
N16
Yes Yes Yes No No No
NFS-320
Yes No No No No No
NFS-640
Yes No No No No No
NFS2-640
Yes No No No No No
NFS-3030
Yes No No No No No
NFS2-3030
Yes Yes Yes No No No
XLS 120
Yes No No No No No
XLS 140-2
Yes No No No No No
XLS 2000
Yes No No No No No
XLS 3000
Yes Yes Yes No No No
Table 7.7: Zone Commands
Command Value Holding Register
NOTE: The first response to an analog point poll is zero. This response is an initialization
confirmation from the gateway.