Metasys N2, Technical Manual

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6 N2 Dialer Module—N2 Dialer Module (NDM)
Terminology used in this document is defined as follows:
Active Device: Defines a type of device the remote NDM will dial out to when reporting
an alarm condition. A facility management system is an example of an active device. If
the phone number is configured as active, a remote ID string is not sent. N2 Open
communication is expected. If N2 communication is not detected for a period of Idle
Time Out, the dialer transmits the remote site ID, an error message, and continues its dial
sequence.
Auxiliary Access: The PC with the Configuration Tool is dialing a remote NDM (either
directly or via a local NDM), or is connected via a null modem cable.
Dedicated Telephone Line: An unshared phone line, strictly dedicated to NDM use. No
other phone devices (modem, FAX, voice) can use this line.
Dial Delay: Defines the number of minutes the NDM delays before redialing after failure
to connect.
Dial In: The action taken by the remote NDM to establish a connection with the local
NDM connected to the facility management system.
Dial-in Control: Dial-in Control is a configuration parameter and when enabled, it
allows the remote NDM to dial in upon detection of an alarm. When disabled, the remote
NDM dials in only when it resets. Possible reset conditions are the following: a
download, a sanity reset, an N2 reset command, a power fail, or if modem is disconnected
or powered down.
Dial Out: The action taken by the local NDM to establish a connection with a remote
site.
Direct Access: The PC with the Configuration Tool is accessing a local or remote NDM
by directly connecting to an N2 Bus via a
MM-CVT101-0.
Disconnect Delay: The time during which the modems stay connected on the phone line.
It is controlled by the local NDM.
Hayes Compatible Modem: Any modem that uses the industry standard Hayes protocol
to set up, dial out, and hang up.
Idle Time Out: The amount of time a remote NDM waits to see N2 Bus traffic after
connection has been made to an “active” phone number. Upon timeout, the NDM hangs
up and continues the dial-in process.
Local N2 Dialer Module: The NDM that is connected directly to a facilities
management system via the N2 Bus. The local NDM accepts N2 commands from the
supervisory system to dial a remote NDM. The local NDM also accepts incoming calls
from the remote NDM.
Modem Connect Time: The amount of time the NDM waits for connection to be
established before hanging up and redialing.
N2 Bus: RS-485 communications bus which operates at 9600 baud.
Passive Device: Defines a type of device the remote NDM will dial out to when
reporting an alarm condition. A printer is an example of a passive device. When a phone
number is configured as passive, after connection is established the remote dialer sends
its remote site name and N2 address, the N2 address of the device generating an alarm,
and a list of N2 addresses of all online devices connected to the remote NDM. The
remote NDM then hangs up. This allows the receiver of the call to identify the remote
site that called in, locate the alarm, and know the online/offline status of devices.
Note:
For passive applications (defined as applications where all primary and
secondary phone numbers in the remote NDM configuration file are for passive
devices), the operator can use the Configuration Tool to dial the remote device
and release the alarm to allow additional alarm notification. See the Passive
Printer Application section in this document for information.
Remote N2 Devices: These are the devices connected to the remote NDM (e.g., AHU,
UNT) via the remote N2 Bus.
Remote N2 Dialer Module: The NDM that is located at the remote site. This NDM
scans the devices on the remote N2 Bus for alarm
Definition of
Terms