Daikin McQuay ED 15117, Информация о протоколе

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ED15117 21
Alarms
Alarms in a Magnitude Chiller Unit Controller are divided into three classes: Faults, Problems, and
Warnings.

Fault Alarms have the highest priority.

Problem Alarms have medium priority.

Warning Alarms have the lowest priority.
Notification
BACnet
Magnitude Chiller Unit Controllers may have their alarms monitored by one of two methods: 1) a
BACnet Binary Output indicating whether any alarms exist, or 2) Alarm value using three BACnet
Analog Value objects.
1. To monitor whether or not any alarms exist, monitor the Alarm Digital Output variable. If the
Present_Value property is a 1, an alarm is active. A value of 0 for the Present_Value property
indicates that there are no active alarms.
2. To monitor alarms by alarm value, read the Present_Value property of the three Alarm Analog
Value objects (Fault Alarm, Problem Alarm and Warning Alarm). The Present_Value displays a
value that corresponds to the highest numbered alarm that is active. It is possible to have multiple
active alarms, but only the highest numbered is displayed. The values for all alarms are described
in the Alarms section tables. If the Present_Value displays a zero, there are no active alarms.
L
ON
W
ORKS
Magnitude Chiller Unit Controllers may have their alarms monitored by one of two methods: 1) by
using the In_alarm attribute of nvoChillerstat or 2) by reading nvoAlarmDescr.
1. The In Alarm attribute of the Chiller Status Network Variable Output (i.e. nvoChillerstat.in_alarm)
indicates whether any alarm is active (1). If the attribute nvoChillerStat.in_alarm displays a zero,
there are no active alarms.
2. To monitor which alarms are currently active, read nvoAlarmDescr. The unit controller can
accommodate 15 simultaneous alarms. Alarm messages are sent sequentially one every five
seconds.
Clearing
BACnet
Magnitude Chiller Unit Controllers has one Binary Value object that can be used to clear alarms;
ClearAlarms Network. A value of 1 will attempt to clear all alarms. Once the alarms are cleared, the
Present_Value of this object goes back to 0.
L
ON
W
ORKS
Magnitude Chiller Unit Controllers have one variable that can be used to clear alarms; nviClearAlarm.
Changing the State portion of this SNVT_switch to a value of 1 will attempt to clear all alarms. Once
the alarms are cleared, the Present_Value of this object goes back to 0. The Value portion of this
SNVT_switch is not used.