If you display a Mimic that contains dynamic data, your client has to request updates for the dynamic data from the server. The amount of time between requests varies according to:
- The configuration of the expression for each dynamic Mimic object. The expression is configured to be associated with the Normal update group or the Fast update group. If it is associated with the Fast update group, your client will request updates for the expression more frequently than it will request updates those expressions associated with the Normal update group.
- The configuration of the Update Rates on the Options window on your client. The Fast setting defines how regularly the client requests updates for those expressions that are associated with the Fast update group. Similarly, the Normal setting defines how regularly the client requests updates for those expressions that are associated with the Normal update group.
Example:
Let’s say that you have a Mimic that contains some expressions that have fast updates enabled and some expressions that use normal updates. The Fast setting for your client PC is set to 0.5 seconds and the Normal setting is 1.0 seconds.
When you first open the Mimic, your client informs the server that it has some tags that should be updated at a maximum of once every half second, and some tags that should be updated at a maximum of once every second. The server then monitors the tags and updates them but only if the source of the tag’s value has changed since the last update.
The data source for one of the ‘fast’ expressions is changing value every quarter of a second. The server monitors this and updates the expression as fast as it can - every 0.5 seconds. The server cannot update the tag every time the source value changes as the source value is changing every 0.25 seconds and the fastest that the server can update the Mimic is every 0.5 seconds.
The data source for one of the ‘normal’ expressions is changing value every hour. This means that on the Mimic, the tag for the expression will also change once per hour even though the Normal update setting is 1 second. This is because the server only updates the Mimic when the source values change, and the update rates define the maximum speeds at which the Mimic can be updated.
You can use the Options window to define the update rate for the Fast and Normal update groups. The settings you define will apply to the Mimics that are displayed on your client PC.
To define the Update Rates:
- Display the Options window.
- Select the Mimics tab.
- Use the Update Rates settings to define the maximum rates at which the server can update the values on a Mimic shown on your client PC:
- Use the Fast spin box to define the maximum rate at which the server can update those expressions that have Fast Updates enabled. The default setting is 0.5 seconds and the Fast update rate should be around twice as frequent as the Normal update setting.
- Use the Normal spin box to define the maximum rate at which the server can update those expressions that have Fast Updates disabled. The Normal update group should be updated at a slower rate than the Fast update group, usually around half as often. By default, the Normal update group is updated every second.
Please be aware that changing the update rates may affect the performance of your system.
- Select the OK button to apply the changes and close the Options window.
The Fast and Normal update rates that you define will only apply to the dynamic data on Mimics that are displayed on your client PC. When the same Mimics are displayed on other clients, they will use the update rates that are defined on those clients’ Options windows.