When an Echo Contact Input Interface is powered on, it waits ~ 60 seconds, then performs actions based on the state and settings of its contacts.
When an Echo Demand Response Interface is powered on, it immediately evaluates its inputs. Any inputs that are closed causes the EDI to share ("beacon") that Echo Power Controllers should perform their Demand Response actions. Any inputs that are open are ignored by the EDI until they change. Note that Echo Demand Response contacts are always Maintained - there is no Momentary option.