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Phase Template: filter-discharge

Break vacuum and discharge dry product from the filter-dryer. Use this phase as the final step of every filter-dryer recipe. It stops the vacuum pump, opens the vent valve to equalize the vessel, then runs the agitator to break up the cake and hold for the discharge time.

Where to find it

System endpoint → Equipment Library → Phases → select filter-discharge.

graph TD
    Start([initial]) --> STV[stop_vacuum]
    STV -->|"vacuum.POS < 5"| OV[open_vent]
    OV -->|"vent.FB"| WA[wait_atmospheric]
    WA -->|"pressure >= 950 mbar"| SA[start_agitator]
    SA -->|"agitator.POS >= 80% speed"| DI[discharging]
    DI -->|"T >= discharge_time"| STA[stop_agitator]
    STA -->|"agitator.POS < 2"| Done([done])

See Phases for the diagram conventions.

What you see when it runs

Element Meaning
Active step Which stage is running — the pump-down is short; most of the time is on discharging
Parameters vent_time, agitator_speed, discharge_time

HMI screenshot pending

An annotated capture of a running filter-discharge phase will be added here.

Parameters

Parameter Type Unit Range Default Required
vent_time TIME — 10s-5m — yes
agitator_speed REAL % 10-100 — yes
discharge_time TIME — 30s-10m — yes

TIME parameters take duration strings ("45s", "1m30s", "5m"), not bare numbers.

Required control modules

Role Module type Description
vent_valve discrete-valve Vent / vacuum break valve
vacuum_controller analog-control Vacuum pump controller
pressure_sensor analog-sensor Vessel headspace pressure
agitator analog-control Agitator for cake breakup during discharge

Capability: filtration.

How it works

Each scan the SFC engine:

  1. stop_vacuum zeroes the vacuum pump and waits for POS < 5 — the pump is stopped before the vent opens so atmospheric inrush doesn't hit a still-running pump.
  2. open_vent opens the vent valve and waits for FB = TRUE.
  3. wait_atmospheric holds until the headspace pressure climbs to ≥ 950 mbar, at which point the vessel is safely at atmospheric.
  4. start_agitator writes agitator_speed to the agitator and waits for POS >= 80% of setpoint.
  5. discharging holds for discharge_time.
  6. stop_agitator zeroes the agitator and waits for POS < 2 before completing.

This is a timed phase with a strict ordering on vent/pump for safety. Pair with a deviation alarm on the discharge valve and a timeoutSeconds backstop. See Phases § Timed phase.

Used in recipes

Try it

  1. HMI endpoint → Batch Execution → + New → sim-filter-dry-m1 → Start
  2. Wait for the discharge step to activate on filter-dryer-1
  3. Watch the ordering: vacuum stops, then vent opens, then agitator runs. The pressure trend shows a clean rise to atmospheric
  4. Open Data endpoint → Trends on pressure_sensor.PV and agitator.CMD to confirm the sequence