28 LonTalk Communication Interface • ACC-SVN100A-EN
Network Variable and Configuration Property Definitions
nviNoiseRdcnReq
Noise reduction Auto/On request, SNVT_switch
This input network variable requests the chiller to enter a mode of operation where the
noise of the unit is reduced. When Noise Reduction is active the chiller reduces speed of
the condenser fans in order to create less noise.
• Default: Uses nciNoiseRdcnReq
• Invalid value: 0xFF, 0xFF
Valid range (uses 2-state definition of SNVT_switch)
nviRequest
Status request input, SNVT_obj_request
Provides a mechanism for the mode of an object to be requested. Default value will be
adopted at power-up or until an update is received. Does not use the receive heartbeat
function. Responses are received through nvoStatus.
Value
byte
State byte
Resulting
interpretation
Any 0 Auto (0)
01Auto (0)
>0 1 On (1)
Any 0xFF Invalid
Structure definition
Item Type
Enumeration
definition
Default
Invalid
value
Object ID Unsigned 16-bit 0 = node object 65535 65535
1 = chiller object
2 to 65535 are not
valid
Object
request
Unsigned 8-bit enum
object_request_t
See next table:
“Object request”
255 255
Object request
Enumeration definition Description
Controller
interpretation
0 = RQ_NORMAL Enable object and
remove override
Report object status
2 = RQ_UPDATE_STATUS Just report object
status
Report object status
5 = RQ_REPORT_MASK Report status bit mask Report status bit mask
9 = RQ_CLEAR_STATUS Clear object status Report object status
10 = RQ_CLEAR_ALARM Clear object alarm Clear object alarm
16 to 255 = RQ_NUL Value not available Ignore object request
Note: Other enumeration definitions for object_request_t, as defined by LonMark, are not used by
the UC800 controller and have no effect on its operation.
