Load Control Events (LCEs)

The Load Control Event (LCE) is an instruction, which originates from the utility company, to schedule a temporary adjustment of consumption in devices that support the DRLC cluster. The contents of an LCE are outlined in Section 41.4.1.

An LCE is sent from the utility company to the DRLC server (ESP) of a ZigBee network, from where it is passed to DRLC clients. The LCEs are held in lists on the server and clients, as described in Section 41.4.2.

LCE handling is described in Section 41.5.

LCE Contents

The information contained in an LCE includes:

  • LCE ID (provided by utility company)

  • Target device class and enrolment group

  • Start-time

  • Duration

  • Criticality level

  • Required adjustment(s)

  • Randomization requirements (for start-time and end-time)

For a full list and description of the LCE data, refer to the description of the LCE structure tsSE_DRLCLoadControlEvent in Section 41.11.1.

Parent topic:Load Control Events (LCEs)

LCE Lists

The DRLC cluster server and clients each hold the following lists of LCEs:

  • **Active list:** Contains LCEs that are currently being executed - it is possible for more than one LCE to be active at the same time, provided that their device classes and enrolment groups do not clash.

  • **Scheduled list:** Contains LCEs that are due to be executed in the future - that is, their start-time is later than the current time.

  • **Cancelled list:** Contains LCEs that have been canceled with a randomized end-time and whose random end-time has not yet been reached.

  • **Deallocated list:** Contains expired LCEs and therefore a record of the free storage for LCEs - used internally by the cluster (and not by the application).

A new LCE is first added to the Scheduled list, unless it has a ‘start-time of now’ in which case it is added to the Active list. An LCE in the Scheduled list is automatically moved to the Active list at the scheduled start-time (or at the randomized start-time). At the end of an active LCE, it is automatically moved to the Deallocated list. However, an active LCE which is canceled with a randomised end-time is automatically moved to the Cancelled list, where it stays until the end-time has been reached (when it is moved to the Deallocated list).

The addition of a new LCE on the cluster server is performed by the server application, as described in Section 41.5.1, but is done automatically by the cluster on the clients. All other operations on LCE lists, apart from cancelation (see Section 41.5.3), are performed automatically by the cluster on both server and client.

Functions are provided to access entries in the local LCE lists:

  • eSE_DRLCGetLoadControlEvent() can be used to obtain a particular LCE entry (with specified list index) in any one of the local lists

  • eSE_DRLCFindLoadControlEvent() can be used to search for and obtain a particular LCE (with specified ID) in any of the local lists

Parent topic:Load Control Events (LCEs)

Parent topic:Demand-Response and Load Control Cluster