Standard Object Support - Danfoss VLT 6000 HVAC Operating Instructions Manual

Example 5: A controller node error is written to VLT
parameter 201, Output Frequency Low Limit,
with 80.0 Hz when the high limit is 60 Hz . The
conversion index is -1, with conversion factor 0.1.
The controller node sends the following
parameter write request to the VLT.
Standard
The VLT LonWorks option supports two
standard objects and three SNVTs, per the
Object
LonMark standard object philosophy. The
Support
standard objects are the Node Object
(containing the Object request, Object status,
and Object alarm) and the Controller object ,
(containing the network variables described
in the preceding sections). The Object request
is a LonMark device used to obtain status and
alarm information from a node.
It is not necessary for a controller to support
the Node Object network variables. The
Object request, Object status and Object
alarm provide status and alarm information
for controllers that only support this type of
functionality. The status and alarm functions
described in the preceding sections contain
more drive specific information than Object
status and Object alarm.
MG.60.N2.02 - VLT is a registered Danfoss trademark
nvoParamCmd.learn =
LN_LEARN_CURRENT
nvoParamCmd.selector = 201
nvoParamCmd.value[0] = 0
nvoParamCmd.value[1] = 0
nvoParamCmd.value[2] = 3 hex
nvoParamCmd.value[3] = 20 hex (800
decimal)
1. The VLT sends an Object status
containing drive status information
and an Object alarm containing fault
informationin response to the
following Object requests :
RQ_NORMAL,
RQ_UPDATE_STATUS, and
RQ_UPDATE_ALARM.
Function
Object request
Object status
Object alarm
Network Variables for Node Object Support
VLT ® 5000 / VLT
The controller node receives the following
parameter access response from the VLT.
SNVT type
SNVT_obj_request
SNVT_obj_status
SNVT_alarm
® 6000 HVAC / VLT
nviParamResp.learn = LN_NULL
nviParamResp.selector = 201
nviParamResp.value[0] = 0
nviParamResp.value[1] = 0
nviParamResp.value[2] = 0
nviParamResp.value[3] = 3 (illegal data
value)
nviParamResp.day = 0
nviParamResp.hour = 0
nviParamResp.minute = 0
nviParamResp.second = 0
nviParamResp.millisecond = 0
The nviRequest.object_id should be set
to "1" (controller node). The network
uses nviRequest, nvoStatus and
nvoAlarm variables for these functions.
2. The VLT sends an Object status
containing a bit map of supported
status fields in response to all other
Object requests, including undefined
requests.
3. The VLT Object status supports the
following status fields: invalid_id,
invalid_request,open_circuit,
out_of_service, electrical_fault,
comm_failure, manual_control, and
in_alarm. All other fields are always
set to "0."
4. The VLT sends an Object alarm
following any set or reset of a drive
fault condition.
5. The Object alarm supports the
AL_ALM_CONDITION and
AL_NO_CONDITION alarm types.
Variable Name
nviRequest
nvoStatus
nvoAlarm
® 8000 AQUA
Input/Output
Input
Output
Output
37