A set of digital and analog tags can be defined that are used to trigger callouts and report register values to the host.
In this screen capture Tags has been selected in the navigation pane and then the form is right clicked to show the drop down. The first menu item has been selected to show that an analog or digital tag can be created.
| Name | Tag name. |
| Type | The type of register: status, coil, holding, or input. |
| Register | Modbus register number. |
| Value | Value of the tag at the time the Get button was clicked. |
| Units | Unit of measure for analog tags and state name for digital tags. |
| Alarm | State of the alarm condition at the time the Get button was clicked. ALARM, OK, or BYPASS. ALARM means the alarm condition has been met. OK means the alarm condition has not been met. BYPASS means the alarm has not been enabled using the Enable check box. If the Alarm check box is not checked then this field is blank. |
Status and coils can be appended, inserted, and modified. Each tag is configured using a pop-up dialog.
| Tag Name | 1 to 32 character descriptive name. |
| Inbound | Enables the inbound transformation. |
| Outbound | Enables the outbound transformation. |
| Register | If checked the tag is associated with a user provided register number. |
| 0 State Name | 1 to 4 character name of the 0 state. |
| 1 State Name | 1 to 4 character name of the 1 state. |
| Enable | Checked if this tag is to be used to trigger an event. |
| Alarm | The detected event is an alarm. |
| Suppress | Suppress event. If checked no callout will be generated due to this event condition. |
| Range | Enables range checking where tag value and delay are used. |
| Change | Enables change in tag value to be used as the event condition. |
| Value | An event is triggered when register transitions to this value. |
| Delay | Amount of time state must be retained for the event to occur. Seconds. |
When an event is generated all the tag values, whether checked or not, and the tag parameters are returned to the host. If the Alarm is set for a tag and that tag is in the alarm condition then the callout is an alarm.
| Bit # | Bit number of the source tag. Lowest order is bit 0. |
| Invert | Inverts the source bit. |
Inputs and holdings can be appended, inserted, and modified. Each tag is configured using a pop-up dialog.
| Tag Name | 1 to 16 character descriptive name. |
| Units | 1 to 6 character name of the units of measure for the tag (i.e. kPa). |
| Register | If checked the tag is associated with a user provided register number. |
| Inbound | Enables the inbound transformation. |
| Outbound | Enables the outbound transformation. |
| Enable | Checked if this tag is to be used to trigger an event. |
| Alarm | The detected event is an alarm. |
| Suppress | Suppress event. If checked no callout will be generated due to this event condition. |
| Range | Enables range checking where tag value and delay are used. |
| Change | Enables change in tag value to be used as the event condition. |
| Lo Low | Event is triggered when register value is less than this. |
| Low | Event is triggered when register value is less than this but not lo low. |
| High | Event is triggered when register value is greater than this but not hi high. |
| Hi High | Event is triggered when register value is greater than this. |
| Delay | Amount of time the alarm condition must be unchanged before an event is triggered. In seconds. |
Transformations of data going into a tag or out of a tag are defined by these forms. Both inbound and outbound forms have a similar layout.
| Format | Format of the internal register (i.e. the bit layout). See table in next section for details. |
| Scaling | Type of scaling to be applied: none, linear, inferred, or fixed. If scaling is set to None then the Lo and Hi values are used directly to generate an event. Also the returned value is a raw value. If scaling is set to Inferred then an implied decimal point is assumed for the raw values. The Decimal parameter indicates the number of digits after the decimal point. For example, if Decimal is 1 and the raw analog value is 102, then 10.2 is the transformed value. If scaling is set to Linear or Fixed then a linear transformation is applied to the raw values. If Linear then the raw input range must be specified in Lo Raw and Hi Raw. If Fixed then then Lo Raw is set to 0 and Hi Raw is set to 32767 automatically. |
| Decimal | Number of decimal places if inferred scaling is used. |
| Lo Raw | Low value of raw range if linear or fixed scaling is used. |
| Hi Raw | High value of raw range if linear or fixed scaling is used. |
| Lo Eng | Low value of scaled range if linear or fixed scaling is used. |
| Hi Eng | High value of scaled range if linear or fixed scaling is used. |
| Clip | Enabled clipping using min and max. |
| Min | Minimum of range that value will be clipped to. |
| Max | Maximum of range that value will be clipped to. |
| Digits | Number of digits to the right of the decimal place displayed in the Tags form. |
| Formatter | Format string to use when displaying the tag value. Presently unused. |
When an event is detected all the tag values, whether checked or not, and the tag parameters are returned to the host. If the Alarm is set for a tag and that tag is in the alarm condition then the callout is an alarm.
The Lo Low, Low, High, Hi High values used to generate the event always refer to the transformed values and not the raw values unless Scaling is set to None. If scaling is set to None then the Lo and Hi values are used directly to generate an event. Also the returned value is a raw value.
The format of the inbound value and outbound value can be one these. The inbound transformation assumes the source is in this format and transforms it into a tag value. The outbound transformation does the inverse.
| 16U | 16 bit unsigned |
| 16S | 16 bit signed |
| 32U_B | 32 bit unsigned, big endian |
| 32U_L | 32 bit unsigned, little endian |
| 32S_B | 32 bit signed, big endian |
| 32S_L | 32 bit signed, little endian |
| 16X2FP_B | two 16 bit registers, floating point, big endian |
| 16X2FP_L | two 16 bit registers, floating point, little endian |
| 32FP_B | 32 bit floating point, big endian |
| 32FP_L | 32 bit floating point, little endian |
The maximum number of tags permitted depends on the terminal variant.
| Variant | Maximum Tags |
|---|---|
| SAT100 | 128 |
| SAT110 | 64 |
| SAT120 | 256 |
| SAT130 | 256 |
| SAT140 | 256 |