Metasys N2, Техническое руководство

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N2 Dialer Module—N2 Dialer Module (NDM) 51
It is not necessary to map any of the remote NDM data points into the Companion data
base. A few communication parameters may be mapped to allow for easy update without
having to enter the Commissioning mode of HVAC PRO for Windows. Refer to Table 17
for a complete summary of mappable points.
One point that may come in handy is the dial-in control point. This controls whether or
not the remote dialer would ever initiate a dial in on an alarm condition. If you are aware
of several system problems at a remote facility and continue to receive reportable alarms,
the point can be set to disable the remote dial ins until the condition is corrected.
To use the dial-in control point, map it into the Companion data base as network point
type BD and software point type AO or BO. For more information on adding points to
the data base, see the Companion technical bulletin.
Table 16: BD-72 Dial-In Control
Value Description
0 Enables dial in on alarm
1 Disables dial in on alarm
The remote NDM polls the remote N2 Bus devices for reportable alarm conditions. If
one is noted, the remote NDM initiates the dial-in sequence through the local NDM to
pass the alarm information on to the facility management system. Mapping binary input
points into the Companion System is one main item that enables a point in a remote
device to generate a reportable alarm.
Simply adding the point to the data base causes the Companion System to enable the COS
reporting for that point in the controller. It is, however, how the priority is defined that
actually enables the dial-in function. If the priority is defined as CRITICAL, then the
remote NDM dials in and reports the COS to the facility management system as defined
in the NDM’s configuration file. A COS is reported both when the point enters alarm and
when it returns to normal. Conversely, if the normal condition is defined as STATUS or
NONE, then the COS condition will not trigger the remote NDM to dial in to report the
change.
Remote NDM--
Software Point
Mapping
Reportable
Changes-of-
State (COS)