Bacharach HGM300 Installation Manual - page 9
There are several ADI points which can provide useful information such as type of
refrigerant programmed for each zone, number of zones actually installed in the HGM,
the number of zones in alarm, HGM operating mode, etc.
Alarm Acknowledge Options
Two alarm acknowledge options are supported—Auto Acknowledge and Network
Acknowledge.
In the Auto Acknowledge mode, the HGM will clear its alarm outputs the next time the
alarmed zone is sampled and its PPM has dropped below the alarm thresholds. No
intervention from the Metasys network is necessary.
In the Network Acknowledge mode, the HGM will never clear its alarm outputs until the
Metasys network connection has acknowledged the Change-of-State alarms reported to
Metasys. Once Metasys has acknowledged the alarm messages, the HGM will clear its
alarm outputs the next time the alarmed zone is sampled and its PPM has dropped below
the alarm thresholds. Please note that the Metasys acknowledgement is a field-level
acknowledgement that takes place automatically (typically within a few seconds). It is
not a human operator acknowledging that the alarm was seen on a console. The Metasys
acknowledgement does, however, mean that the system has caught the alarm and that it
will be reported to some higher level.
Dipswitch A1 on the adapter selects which alarm acknowledge option is used:
A1 On = Auto Acknowledge
A1 Off = Network Acknowledge
Operating Limitations When Using RDM800 Remote Display
When an RDM800 remote display is used, the N2 network will have access to the
HGM300 as long as the RDM800 is in either the SYSTEM or ZONE VIEW screen. If
the RDM800 is set to display any other screen, it will respond to polls from the N2
adapter with an HGM BUSY exception code. The N2 adapter will handle the exception
by marking most points as Unavailable and setting the Unavailable Reason point = HGM
Busy. When the RDM800 is returned to the SYSTEM or ZONE VIEW screen, normal
N2 monitoring will resume.
If the operator leaves the RDM800 in some screen other than SYSTEM or ZONE VIEW
for an extended period of time (10 minutes default), the RDM800 times out and
automatically returns to either the SYSTEM or ZONE VIEW screen. This will restore
normal N2 monitoring.
9 of 10