Link control and proxy points

As proxy points have no inputs, you cannot link into them from local station logic even if the remote source component is a writable point. To configure inter-station link control, make another proxy point in the remote station that proxies whatever local source component you need for the link.

For example, consider a proxy point for a BooleanWritable that controls a fan. To provide link control from a local And object, which controls at priority level seven, your wire sheet might look like this:

Figure 1. Local object cannot link into a proxy point

In the example, you cannot link into the proxy point BFanBO_1. So, the remote station must make a proxy point for the And object, then link its output to the source point for BFanBO_1.

Figure 2. Source control object now a proxy point in the remote station

The example shows the wire sheet views with the source point and And objects.

In a typical Supervisor station that serves primarily Px views not much direct link control is needed so this rarely applies. In addition, the schedule import and export mechanism provides central scheduling control using local (imported) schedule components. However, if you are configuring applications between remote stations that require link control, always use proxy points in this fashion.