LonWorks Export Module
The LonWorks Export Module allows your ION meter to provide data to a LonWorks network.
Module icon
Overview
NOTE: The LonWorks Export Module is available only on certain meters (those with older firmware).
This module converts ION register values to LonWorks output network variables. As discussed below, these output network variables must be one of the standard network variable types (SNVTs) as specified by the SNVT setup register.
For more information about LonWorks networks, visit the LonMark website at www.LonMark.org
NOTE: The registers and settings available in this module depend on the device or node you are configuring, as well as its firmware and template versions. Not all registers or settings are available on all devices or the Virtual Processor, and labels may vary.
Output Network Variable Name
The name of the network variable is determined by the module’s label. Although the default label will work, it is good practice to use custom label names that identify the data source and LonWorks variable type. For example, if the module’s Source input is linked to the Power Meter module’s output register Vln a, a descriptive output network variable name would be nvoVln_a.
Inputs
Source
This input value is converted to a LonWorks output network variable and delivered to the LonWorks network. The data type of the output network variable is defined by the SNVT setup register. You must link the Source input for the LonWorks Export module to function.
Setup registers
Send Time
This register specifies the maximum number of seconds that can elapse before the output network variable is updated. In other words, the output network variable will be updated at a frequency dictated by this setup register, even when the source remains constant. Specifying 0 disables this parameter. Each time the network variable is updated, Send Time is reset.
Send Delta
This
register specifies how much the Source input
must change before the output network variable is updated. It is specified
as an absolute value. If you specify 0, the output network variable
will be updated every time the Source input changes.
The output network variable will be updated if the following condition
is true:
Update Rate Examples
The Send Delta and Send Time setup registers are not mutually exclusive. The following table illustrates how the combination of the two register values influences the module’s operation.
| Conditions | Update Response |
|---|---|
|
Send Time = 0 Send Delta = 0 |
Update the network variable every time the Source input changes |
|
Send Delta = 5 Send Time = 0 |
Only update the network variable if Source differs from the previous value of the network variable by ±5 units |
|
Send Delta = 0 Send Time = 5 |
Update the network variable every time Source changes or, if Source is not changing, every 5 seconds |
|
Send Delta = 7 Send Time = 3 |
Update the network variable if Source differs from the previous value of the network variable by ±7 units or, after 3 seconds have elapsed since the last network variable update |
SNVT
This register defines Standard Network Variable Type (SNVT). Two nodes in a LonWorks network can only share information if they export/import the same data type. The SNVT indicates what kind of data the LonWorks Export module is placing onto the LonWorks network. In effect, the SNVT associates a unit with the data value. For example, if you want to convert an ION register reporting energy (kWh) to a network variable, set the SNVT setup register to SNVT_elec_kwh. Refer to the table of supported SNVTs towards the end of this module description. More details about each SNVT can be found in the LonMark’s SNVT Master List.
NOTE: Be aware that if the LonWorks Export module’s network variable is currently bound (i.e. BindState is on), you cannot change this setup register. You must first unbind the network variable using LonWorks Network Manager software.
Output registers
LonWorks Export Modules have an output register that delivers the LonWorks network variables. A network variable has two components: the converted value from the Source input, and the units that are specified by the SNVT setup register.
BindState
This register indicates that the module’s output network variable is bound to at least one other LonWorks network variable. See “Binding Network Variables”.
Event
All events produced by a LonWorks Export module are written into this register. Events include changing the SNVT setup registers, changing the links to its input, and the BindState output register changing state. The Event output register stores the following information for each ION event: time stamp, event priority (in this module, all events have a pre-defined priority of 10), the event’s cause, the event’s effect, and conditions associated with the event’s cause and effect.
Responses to special conditions
The following table summarizes how the module behaves under different conditions:
| Condition | Response |
|---|---|
| Module is first created (module’s default configuration) | The network variable will be set to zero and the SNVT setup register will be set to SNVT_not_used. If the SNVT setup register is set to anything other than SNVT_not_used, the network variable will be set to its exception value. * |
| Source input is not linked | The network variable will be set to the exception value and will not be updated. |
| Source input is not available | The network variable will be set to the exception value and is updated according to the Send Time and Send Delta setup registers. |
| If Source input is outside the range supported by the SNVT | The network variable will have its minimum possible value (if Source is too small) or its maximum possible value (if Source is too large). |
| During a firmware upgrade | The network variable will retain the last updated value. |
| Module is deleted | The network variable will be forced to the exception value. |
| * Some SNVT types support a specific exception value. Others will go to their min value to indicate an exception. | |
NOTE: If the network variable is bound, you cannot delete the LonWorks Export module. You must first unbind it using a LonWorks network manager.
Detailed module operation
The following diagram illustrates an ION meter collecting power-system data and converting it to an output network variable in a LonWorks network. The target device is in the upper left corner. The output network variable must be of the same type (SNVT) as the input network variable.
NOTE: Note: If you create any new LonWorks Export modules or you change their SNVT types, you will have to reinstall and reconfigure the device on the LonWorks Network for your changes to be detected.
Binding Network Variables
The network variable is bound if the module’s BindStatus output is on. Your LonWorks Export modules may already be bound to certain common measurements (and further configuration may not be necessary). By default, the LonWorks Export module will use the SNVT_not_used (the first register in the SNVT setup register list).
Binding and unbinding network variables is accomplished with LonWorks Network manager tools. There are a number of tools available, each with their own configuration procedures. Refer to the documentation of network tools you are using for more details.
Supported SNVTs
The
|
Measurement |
SNVT Name |
Range |
Resolution |
SNVT # |
Exception Value |
|---|---|---|---|---|---|
|
SNVT_not_used |
|||||
|
Current (integer) |
SNVT_amp |
-3,276.8 .. 3,276.7 A |
0.1 A |
1 |
-3,276.8 A |
|
Current (float) |
SNVT_amp_f |
-1E38 .. 1E38 A |
48 |
-1E38 A |
|
|
Current [milli] (integer) |
SNVT_amp_mil |
-3,276.8 .. 3,276.7 mA |
0.1 mA |
2 |
-3,276.8 mA |
|
Phase/Rotation [degree] (integer) |
SNVT_angle_deg |
-359.98 .. 360.00 deg |
0.02 deg |
104 |
655.34 deg |
|
Phase/Rotation (float) |
SNVT_angle_f |
-1E38 .. 1E38 radians |
49 |
-1E38 rads |
|
|
Energy, thermal (float) |
SNVT_btu_f |
-1E38 .. 1E38 BTU |
67 |
-1E38 BTU |
|
|
Energy, thermal [kilo] (integer) |
SNVT_btu_kilo |
0 .. 65,535 kBTU |
1 kBTU |
5 |
0 kBTU |
|
Energy, thermal [mega] (integer) |
SNVT_btu_mega |
0 .. 65,535 MBTU |
1 MBTU |
6 |
0 MBTU |
|
Count, event (integer) |
SNVT_count |
0 .. 65,535 counts |
1 count |
8 |
0 counts |
|
Count, event (float) |
SNVT_count_f |
-1E38 .. 1E38 counts |
51 |
-1E38 counts |
|
|
Count, incremental (integer) |
SNVT_count_inc |
-32,768 .. 32,767 counts |
1 count |
9 |
-32,768 counts |
|
Count, incremental (float) |
SNVT_count_inc_f |
-1E38 .. 1E38 counts |
52 |
-1E38 counts |
|
|
Energy, electrical [kilo] (integer) |
SNVT_elec_kwh |
0 .. 65,535 kWh |
1 kWh |
13 |
0 kWh |
|
Energy, electrical (integer) |
SNVT_elec_whr |
0 .. 6,553.5 Wh |
0.1 Wh |
14 |
0 Wh |
|
Energy, electrical (float) |
SNVT_elec_whr_f |
0 .. 1E38 Wh |
68 |
0 Wh |
|
|
Flow (integer) |
SNVT_flow |
0 .. 65,534 l/s |
1 l/s |
15 |
65,535 l/s |
|
Flow (float) |
SNVT_flow_f |
-1E38 .. 1E38 l/s |
53 |
-1E38 l/s |
|
|
Frequency (float) |
SNVT_freq_f |
-1E38 .. 1E38 Hz |
75 |
-1E38 Hz |
|
|
Frequency (integer) |
SNVT_freq_hz |
0 .. 6,553.5 Hz |
0.1 Hz |
76 |
0 Hz |
|
Level, continuous (integer) |
SNVT_lev_cont |
0 .. 100% |
0.50% |
21 |
0% |
|
Level, continuous (float) |
SNVT_lev_cont_f |
0 .. 100% |
55 |
0% |
|
|
Level, discrete |
SNVT_lev_disc |
ST_OFF, ST_LOW .. ST_ON |
¼ level |
22 |
ST_NUL |
|
Level, percent |
SNVT_lev_percent |
-163.84% .. 163.83% |
0.005% or 50 ppm |
81 |
163.84% |
|
Power (integer) |
SNVT_power |
0 .. 6,553.5 W |
0.1 W |
27 |
0 W |
|
Power (float) |
SNVT_power_f |
-1E38 .. 1E38 W |
57 |
-1E38 W |
|
|
Power [kilo] (integer) |
SNVT_power_kilo |
0 .. 6,553.5 kW |
0.1 kW |
28 |
0 kW |
|
Pressure - absolute (float) |
SNVT_press_f |
0 .. 1E38 Pa |
59 |
0 Pa |
|
|
Pressure - gauge (integer) |
SNVT_press_p |
-32,768 .. 32,766 Pa |
1 Pa |
113 |
32,767 Pa |
|
Power factor (integer) |
SNVT_pwr_fact |
-1.0 .. 1.0 |
0.00005 |
98 |
-1 |
|
Power factor (float) |
SNVT_pwr_fact_f |
-1.0 .. 1.0 |
99 |
-1 |
|
|
Angular Velocity [RPM] (integer) |
SNVT_rpm |
0 .. 65,534 revs/min |
1 rev/min |
102 |
65,535 revs/min |
|
Temperature (integer) |
SNVT_temp |
-274 .. 6,279.5 °C |
0.1 °C |
39 |
-274 °C |
|
Temperature (float) |
SNVT_temp_f |
-273.17 .. 1E38 °C |
63 |
-273.17 °C |
|
|
Temperature [HVAC] (integer) |
SNVT_temp_p |
-273.17 .. 327.66 °C |
0.1 °C |
105 |
327.67 °C |
|
Time - elapsed (float) |
SNVT_time_f |
-1E38 .. 1E38 s |
64 |
-1E38 s |
|
|
Time - elapsed (integer) |
SNVT_time_sec |
0.0 .. 6,553.4 s |
0.1 s |
107 |
6,553.5 s |
|
Voltage (integer) |
SNVT_volt |
-3,276.8 .. 3,276.7 V |
0.1 V |
44 |
-3,276.8 V |
|
Voltage (float) |
SNVT_volt_f |
-1E38 .. 1E38 V |
66 |
-1E38 V |
|
|
Voltage [milli] (integer) |
SNVT_volt_mil |
-3,276.8 .. 3,276.7 mV |
0.1 mV |
47 |
-3,276.8 mV |