To use DLLR, you must have a least one piece of equipment that DLLR can control. You then must assign a Load extension to the Metasys object representing this equipment. The Load extension describes how DLLR can control the equipment. Next, you create a DLLR object and associate the Load extension to the DLLR object. If you plan to use the Demand Limiting portion, a meter object is also required, which is referenced in the DLLR object. Meter objects can be one of several objects offered in the system as discussed in Demand Meter Object.
You can define the DLLR object and its associated Load extensions offline using the System Configuration Tool (SCT) or online by connecting to the Site Director via Web browser. We recommend that you use SCT to define DLLR, as similar Load extensions can be copied and pasted quickly.
The DLLR object indicates which loads are being shed and the overall load strategy used. Each Load extension also is configured for a shed strategy (DLLR, DL, or LR) and a load priority (1 to 10, with 1 as the highest priority). The shed strategy defines the purpose for which the load can be shed, and the load priority affects how often it may be shed. These values are defined by the Load Extension Shed Strategy and Load Priority attributes. Because the DLLR object determines the action the system performs, if you have conflicting strategies defined in the DLLR object and Load extension, the setting in the DLLR object setting is used. For example, if the DLLR object Shed Strategy is set to DL only, and a Load Extension is set to only LR, no action takes place. If a load is shed for one strategy, it is not available to be shed again for either strategy until its minimum release time expires.
You can define as many DLLR objects and Load extensions as memory in the engine allows. Engines include the Network Automation Engine (NAE), Network Control Engine (NCE), and Network Integration Engine (NIE). If you reach the limit for loads, the message The Load references exceed the maximum size appears.
Load extensions do not need to reside on the same engine as the DLLR object, but this setup is recommended. The Load extension and DLLR object must reside on the same site.
You can define only one Load extension per object. See Chiller/Boiler Step Strategy for an example of an application with logic needed to work around this restriction.
In general, we strongly recommend the following:
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Define the meter object on the same engine as the DLLR object.
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Associate each Load extension with only one DLLR object. But, one DLLR object may have many different loads.
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Do not use an N1 Migration object for the meter unless you can guarantee that the Network Communication Module (NCM) service time is always less than 60 seconds. The DLLR algorithm requires an updated meter value every minute.