DEMAND_LIMIT_CTRL
Electrical demand limiting: priority load shedding on a filtered demand estimate, with a fast overload path and rebound-free restoration.
When to use it
Use DEMAND_LIMIT_CTRL when a building's electrical demand has to be kept under a target — a tariff demand charge, a utility curtailment signal or a generator's capacity — by shedding non-critical load groups in priority order.
Interface
The published port signature. This is the whole of what the block exposes to your program — the implementation body is not shown here and ships with the download.
Inputs
| Port | Type | Unit |
|---|---|---|
| ENABLE | BOOL | — |
| KW_NOW | REAL | kW |
| KW_OK | BOOL | — |
| KW_LIMIT | REAL | kW |
| PRIORITY | USINT | — |
| AVG_TAU | REAL | s |
| RESTORE_MARGIN | REAL | kW |
| SHED_STEP | TIME | — |
| FAST_STEP | TIME | — |
| FAST_FRAC | REAL | fraction |
| RESTORE_STEP | TIME | — |
| ACK | BOOL | — |
Outputs
| Port | Type | Unit |
|---|---|---|
| SHED_LEVEL | USINT | — |
| LOADS_SHED | UINT | — |
| KW_AVG | REAL | kW |
| SHEDDING | BOOL | — |
| ALM_MAX_SHED | BOOL | — |
| ALM_OVER_LIMIT | BOOL | — |
| ALM_KW_FAULT | BOOL | — |
| ALM_CFG_ERR | BOOL | — |
IEC 61499 event interface
EI INIT, REQ·EO INITO, CNF
Validation evidence
- Tests
- 8
- Simulated scans
- 324
- Simulator
- v0.1.0
Complete IEC 61131-3 implementation with a published test suite that runs on the vplant simulator. The counts above are that suite, executed on this build.
- Conforms to IEC 61131-3
- Conforms to IEC 61499
Download DEMAND_LIMIT_CTRL — free
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