PUMP_ALTERNATOR
Three-pump duty alternation: maps a call count onto the least-used available pumps, with swap hysteresis so a running duty pump is not handed off mid-run.
When to use it
Use PUMP_ALTERNATOR when two or three interchangeable pumps share one duty and the station wants wear shared by run-hours rather than by a fixed lead/lag assignment.
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 | — |
| N_CALL | USINT | — |
| H1 | LREAL | h |
| H2 | LREAL | h |
| H3 | LREAL | h |
| P1_AVAIL | BOOL | — |
| P2_AVAIL | BOOL | — |
| P3_AVAIL | BOOL | — |
| ROTATE | BOOL | — |
| SWAP_HYST_H | REAL | h |
Outputs
| Port | Type |
|---|---|
| RUN_1 | BOOL |
| RUN_2 | BOOL |
| RUN_3 | BOOL |
| N_RUN | USINT |
| LEAD_PUMP | USINT |
| ALM_INSUFFICIENT | BOOL |
| ALM_NONE_AVAIL | BOOL |
IEC 61499 event interface
EI INIT, REQ·EO INITO, CNF
Supervised control write
PUMP_ALTERNATOR commands a real actuator. It is written to sit underneath your own interlock, permissive and protection logic — not to replace it. Commission it as you would any control block you wrote yourself.
Validation evidence
- Tests
- 7
- Simulated scans
- 40
- 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 PUMP_ALTERNATOR — free
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