---
name: evolv-alarms-interlocks-permissives
description: Design and review alarms, interlocks, and permissive logic for EVOLV control nodes. Use when implementing trip conditions, permissive checks, startup/shutdown guards, alarm priorities, latching/reset behavior, and operator-facing fault handling.
---

# EVOLV Alarms Interlocks Permissives

## Mission
Make alarm and interlock behavior explicit, testable, and operationally safe while preserving availability-first policy bounds.

## Harness Execution Contract
- Build alarm/interlock map from current node contracts and state logic.
- Define invariants before edits:
  - trips/permissives are deterministic
  - latching/reset behavior is explicit
  - operator-visible diagnostics are preserved
- Validate with sequence and fail-state tests.

## Scope
- `nodes/pumpingStation/`
- `nodes/machineGroupControl/`
- `nodes/rotatingMachine/`
- Any node with mode/state transitions and protective actions

## Workflow
1. Enumerate alarm conditions and priority/severity.
2. Define interlock and permissive truth tables.
3. Verify startup/shutdown/emergency sequences.
4. Confirm reset, auto-recovery, and manual acknowledgement behavior.
5. Ensure outputs expose actionable fault context.

## Standards
- Avoid hidden permissives; every gate should be observable.
- Keep alarm naming stable and semantically clear.
- Separate advisory warnings from trip-level protection.
- Preserve controlled compatibility for released fault topics.

## Test Expectations
Cover:
- trip activation and reset/latch behavior
- permissive-denied and permissive-restored transitions
- out-of-order signal handling in sequence transitions
- degraded sensor quality paths and alarm escalation

## Deliverables
Return:
- alarm/interlock/permissive matrix
- changed files/tests and evidence
- unresolved protection-vs-availability tradeoffs

Decision interview triggers:
- changed trip thresholds or permissive logic with operational impact
- altered reset authority (auto vs manual)
- alarm contract changes affecting external consumers