Id
The Id field shows the internal number under which the channel is stored internally. When a new element is created, the field is empty. The number is for display only and is assigned automatically by the system.
Interface
Here you can see which interface the channel belongs to and what type the interface is. This information is for display only.
Name
The name of the channel. The name is shown in selection lists and may also be visible to the user (e.g. when the channel is displayed in a chart or when a notification originates from or refers to the channel).
Comment
The comment field is available for free use by the integrator/system administrator. It serves solely to document the configuration. Here you can store information such as the purpose of the channel, remarks on the connected hardware, room/floor and other particulars. The content of this field has no meaning for X2.
Option: Persistent
If you check this checkbox, X2 stores the current value of the channel persistently (after a restart, the channel will then have the last value set). If the checkbox is cleared, the channel has no value after a restart until it is either written or a value has been read from the interface.
Option: Chart
Check this checkbox to have the channel's value recorded. Channels whose values are recorded can be displayed as graphs in charts. This is suitable for measured values (temperature, humidity, etc.). The average value over a period of 5 minutes is calculated and stored every 5 minutes. The system automatically detects when the channel is used for a chart and then records data even if you do not check the checkbox. You must check the checkbox yourself if you want the data to be recorded regardless of whether the channel is used in charts.
Write/Read
Defines the access mode for the channel: read, write or both. Depending on the interface, this field may not be editable.
Cyclic writing
Here you can specify that the last written value of the channel is output again to the connected hardware at defined intervals. This setting can only be changed for certain interfaces.
Unit
Defines the value unit and thus also the data type of the channel. If the Autoconfig checkbox is checked, some interfaces can override the unit or lock the setting.
Device type
Device type of the channel (empty for user-defined channels/devices)
Device Id / Slave Id
Modbus slave ID whose register is addressed (1 … 247). You set the slave ID on the Modbus device.
Register no.
Register that is addressed. Valid register numbers are in the range 0 to 65535. The register number must be prefixed with a type digit that indicates the register type (0, 1, 3 or 4). The device documentation usually explains whether counting starts at 0 or 1 (in the latter case, you must subtract 1 from the register address). Depending on the manufacturer, the type digit may or may not be specified as part of the register address. This can lead to ambiguities, e.g. "40000" can mean either type 4, register 0 or no type, register 40000 (therefore check the documentation carefully).
| Register type | First digit | Example |
|---|---|---|
| Coil | 0 | 00001 (Coil number 1) |
| Discrete Input | 1 | 10004 (Discrete Input 4) |
| Input Register | 3 | 30005 (Input Register 5) |
| Holding Register | 4 | 40083 (Holding Register 83) |
Register addresses can also be specified in hexadecimal; to do so, write an 'x' after the type digit followed by 1 to 4 hexadecimal digits (0-9, A-F).
| Register type | First digit | Example |
|---|---|---|
| Coil | 0 | 0x8000 (Coil number 32768) |
| Discrete Input | 1 | 1xFFFF (Discrete Input 65535) |
| Input Register | 3 | 3x000A (Input Register 10) |
| Holding Register | 4 | 4×0020 (Holding Register 32) |
Size / Count
Registers of types 3 and 4 are always 16 bits in size; if that is not sufficient, the device uses several consecutive registers together to represent a value. Refer to the device documentation for the number of registers. Registers of types 0 and 1 are always single bits.
Data type
Here you specify how the register must be interpreted to obtain a meaningful value. The data types are usually explained in the device documentation. If the device defines very unusual data types for which X2 has no matching data type, you can define the register as "Signed" or "Unsigned" and convert it with a formula if necessary. For coil/discrete input registers, select the data type "Bit" or "Boolean".
If the device is provided by X2 and the register is known, "Device-Defined" is shown here. This setting is only permitted if a device type is specified and the register number is defined in the device.
Read interval
How often this register is to be read (updated). Depending on the configuration, the register may be read more often than specified. The reason is that consecutive registers may be combined by the system into a block that is always read together.