All primary blocks have a scan time. The scan time determines how often SAC processes the block and sends the current value to the next block in the chain. SAC processes all secondary blocks chained to a primary block according to the primary block's scan time.
SAC can process a chain using one of the following methods:
Time-based processing is best used when you want to regularly scan a block. If you only need to scan a block when its value changes, use exception-based processing instead. Similarly, you can use one shot processing if you need to scan a block when the process database initially loads.
