VAR_PRIMARY_PUMP
Variable-primary pumping on differential pressure, with a proportional minimum-flow bypass and a latched low-flow alarm.
When to use it
Use VAR_PRIMARY_PUMP when variable-speed primary pumps circulate through the chillers or boilers themselves and must hold a differential-pressure setpoint at the index run while never letting flow fall below the equipment minimum.
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 | — |
| DP_SP | REAL | kPa |
| DP_PV | REAL | kPa |
| DP_OK | BOOL | — |
| MIN_FLOW | REAL | L/s |
| FLOW | REAL | L/s |
| FLOW_OK | BOOL | — |
| BYP_BAND | REAL | L/s |
| KP | REAL | %/kPa |
| TI | TIME | — |
| SPD_MIN | REAL | % |
| SPD_MAX | REAL | % |
| SPD_START | REAL | % |
| FAIL_SPEED | REAL | % |
| LOW_FLOW_TMO | TIME | — |
| ACK | BOOL | — |
Outputs
| Port | Type | Unit |
|---|---|---|
| PUMP_SPEED | REAL | % |
| MINFLOW_VLV | REAL | % |
| VALID | BOOL | — |
| ALM_LOW_FLOW | BOOL | — |
| ALM_SENSOR | BOOL | — |
| ALM_CFG_ERR | BOOL | — |
IEC 61499 event interface
EI INIT, REQ·EO INITO, CNF
Validation evidence
- Tests
- 8
- Simulated scans
- 520
- 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 VAR_PRIMARY_PUMP — free
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