Priority Assignment; Present Value Property Access; Notification Class Object; Savings - Carrier 30XW User Manual

4.3 Priority assignment

Commanding entities have their priority level assigned. The BACnet priority level
corresponds to the CCN override level.
If the Local Operating Type is set to Network, then it is possible to control the unit from
the BACnet writing these objects:
 The highest priority value of the commandable object will be copied to the present
value of the object using the same name with the _rd suffix
(e.g., GENUNIT_CTRL_PNT_wr highest priority value copied to
GENUNIT_CTRL_PNT_rd present value).
If the Local Operating Type is set to Local or Remote, then the Priority value won't be
applied and the value determined by the controller will be applied:
 The present value of the object name with the _rd suffix will still reflect the
current software value (e.g., GENUNIT_CTRL_PNT_rd).
 The BACnet priority level corresponds to the CCN override level (1:1). If this BACnet
priority level is removed, the first non-NULL value in Priority_array property will be
applied to the corresponding CCN point (CCN "Auto" command will be applied first).
 When the CCN override level is applied from the CCN, the CCN override level will be
the BACnet priority level.
 BACnet priority level 16 (the lowest) has no CCN equivalent and does not correspond
to the CCN override. This priority level should not be used.
*The Priority_Array consists of an array of commanded values in order of decreasing priority. The first value
in the array corresponds to priority 1 (highest prority), the second value corresponds to priority 2, etc. The
sixteenth value corresponds to priority 16 (lowest prority).

4.4 Present Value property access

Writing AV and BV "Present Value" is authorized by the BACnet protocol for all objects.
However, the Present value regarding the access object parameters (read-only or
read/write) may or may not be authorised by the chiller application.
If the "present value" property with an access parameter equal to RO is written, then the
present value will be overwritten by the chiller application with the previous value.
Objects with "present value" in read-only access are all objects used for chiller
configuration and status.
Objects with "present value" in read/write access are objects used for setpoint
configuration, i.e. objects with names with the SETPOINT_ prefix (e.g., SETPOINT_csp1)
and Commandable objects with the _wr suffix (e.g., GENUNIT_CTRL_PNT_wr).

4.5 Notification class object

The notification class object can notify up to 5 BACnet devices. These devices are listed
in the Recipient List property.
IMPORTANT
You must enter the IP address of the device to notify (see also section 6).
Device Name and instance are not yet supported.

4.6 Savings

COV increment property, Intrinsic Reporting properties, Priority values, Notification class
and Trend log properties are saved in files and restored automatically on power-up.
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ECG–UG–14-002
30XAXW
BACnet Option
REVISION
Rev G March 2017
DATE PAGE
14 OF 56
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