Options Tab
Display the properties window (‘configuration Form’) for a ROC Plus Scanner object and then select the Options tab.
In the entries below, the OPC tag name is listed in parentheses next to the field’s label:
- Enabled (Tag: $Config.InService). Select this check box for the scanner to be in service.
- Severity (Tag: $Config.Severity). Use this combo box to set the alarm severity for the scanner.
- Channel (Tag: $Config.ChannelId). Select the browse button to display a Reference browse window. Use the window to locate and select the ROC Plus Channel object with which the Scanner object is associated.
- Host Unit Address (Tag: $Config.HostUnitAddress). Use this field to specify the ROC Plus Protocol unit address that the driver uses to communicate with the ROC.
- Host Group Address (Tag: $Config.HostGroupAddress). Use this field to specify the ROC Plus Protocol group address that the driver uses to communicate with the ROC.
- ROC Unit Address (Tag: $Config.RemoteUnitAddress). Use this field to specify the ROC Plus Protocol unit address of the ROC with which the driver is communicating.
- ROC Group Address (Tag: $Config.RemoteGroupAddress). Use this field to specify the ROC Plus Protocol group address of the ROC with which the driver is communicating.
- ROC Security is Enabled (Tag: $Config.SecurityEnabled). Check this box if security is enabled on the ROC. When this box is checked, the driver will log into the ROC before retrieving data.
- ROC User ID (Tag: $Config.UserId). This is the username that the driver uses to log into the ROC. The driver needs to log into the ROC to change the clock, for example. This field is not editable if security in the ROC is disabled, as indicated by the ROC Security is Enabled setting.
- ROC Password (Tag: $Config.Password). This is the password for the ROC. This field is not editable if security in the ROC is disabled, as indicated by the ROC Security is Enabled setting.
- Scan Rate (Tag: $Config.ScanRate). Use this field to specify how often the scanner will poll the ROC and update the points that reference this ROC Plus Scanner.
- Scan Offset (Tag: $Config.ScanOffset). Use this field to specify the offset to the scan rate. For example, if you enter ‘Hour’ in this field, the ROC Plus Scanner will poll at the hour, and then at whatever rate is specified in the Scan Rate field.
- Promoted Scan Rate (Tag: $Config.PromotedScanRate). Use this field to specify how often the scanner will poll the ROC and update the points that reference this ROC Plus Scanner when promoted scanning is enabled. To enable promoted scanning, call the Enable Promoted Scanning method on the ROC Plus Scanner.
- Promoted Scan Offset (Tag: $Config.PromotedScanOffset). Use this field to specify the offset to the promoted scan rate. For example, if you enter ‘Hour’ in this field, the ROC Plus Scanner will poll at the hour, and then at whatever rate is specified in the Promoted Scan Rate field, when promoted scanning is enabled.
- Meter Name (Tag: $Config.MeterName). This field is optional. Whatever text you enter here is populated in the ‘MeterName’ columns of the ROC Plus Event Data table and ROC Plus Alarm Data table. Because the Event and Alarm Data tables can hold data for more than one ROC, the Meter Name field provides a convenient way to filter events from different devices. If you are not getting events or alarms via this scanner, then this field can be left blank.
- Get Events on Scan (Tag: $Config.GetEventsOnScan). Select this check box if the ROC Plus Scanner is to poll for new events on each scan. If this box is selected, ensure that the Event Data Table reference field is populated correctly (see below).
- Event Data Table (Tag: $Config.EventTable). If the Get Events on Scan check box is selected, this field has to contain a reference to a ROC Plus Event Data table. For further information, (see Event Data Table).
- Get Alarms on Scan (Tag: $Config.GetAlarmsOnScan). Select this check box if the ROC Plus Scanner is to poll for new alarms on each scan. If this box is selected, ensure that the Alarm Data Table reference field is populated correctly (see below).
- Alarm Data Table (Tag: $Config.AlarmTable). If the Get Alarms on Scan check box is selected, this field has to contain a reference to a ROC Plus Alarm Data Table. For further information, (see Alarm Data Table).
- Read Clock (Tag: $Config.ReadClockOnScan). Select this check box for the ROC Plus Scanner to read the clock in the ROC on each scan and populate the TimeLocal data field with the time that is read. The driver also updates the ClockOffsetToHostSecs field, which contains the difference between the ROC clock and the Geo SCADA Expert clock.
- Set Clock (Tag:$ Config.SetClockOnScan). Select this check box for the ROC Plus Scanner to read the clock in the ROC on each scan and update the TimeLocal data field on the scanner object with the time that is read. If the difference between the ROC clock and the host clock is greater than the number of seconds specified in the Maximum Clock Offset field (see below), then the clock in the ROC is set to the time at the host, plus the offset (if any) from the ROC Time Zone field.
The comparison is done based on standard time only. The driver will not change the clock in the ROC due to daylight savings time adjustments. When daylight savings time occurs, UTC time does not change, but local time changes its offset to UTC. For example, in the winter, during standard time, if local time is UTC-07:00, then during daylight savings time local time is changed to UTC-06:00.
By not accounting for daylight savings time, the ROC clock stays synchronized to UTC and does not have any jumps. If you want the clock in the ROC to change for daylight savings time, set the ROC Time Zone field to local time -1 hour and call the SetClock method on the scanner, or wait for the next scan. To adjust back to standard time, set the ROC Time Zone field to Local.
- Maximum Clock Offset (Tag: $Config.MaximumClockOffset). This field only applies when the Set Clock check box is selected. Use the field to specify the maximum allowable difference between the host clock and the ROC clock in seconds. If the offset between the two clocks is greater than the number of seconds in this field when the driver scans the ROC, the driver will set the time in the ROC to the host time, plus any offset from the ROC Time Zone field.
- ROC Time Zone (Tag: $Config.TimeZone). This field has a pre-populated selection of possible time zones for the ROC. It is strongly recommended that you leave this setting at Local, but the option to change it is provided as a convenience for advanced users who understand exactly how timestamps work in Geo SCADA Expert, both in how they are stored in the database and how they are translated when viewed in ViewX or Virtual ViewX. There is quite a bit of complexity that results from manipulating the time stamps that are on historic data, events, and alarms from a flow computer. If you leave the time zone setting at Local, much of this complexity disappears.