How-To: Let PELS Manage Device Power Usage

Use this pattern when a device can run at different power levels, and you want PELS to select the best level automatically based on available headroom.

Typical devices:

• water heaters with Low/Medium/Max
• EV chargers with stepped current/power levels
• other controllable loads with discrete states

Figure 1. Example of level selection based on headroom.

Figure 2. Example of expected-power updates when level changes.

What You Are Building

One flow pattern with two ideas:

1. Level selection from headroom Choose the strongest level that fits current headroom.

2. Expected-power sync When the level changes, immediately tell PELS what power to expect.

You can keep this in one Advanced Flow with branches, or split into two separate flows.

Why This Works

PELS decisions depend on expected device usage.

If a device drops from high to medium or low, but PELS still expects the old high value, headroom checks become too conservative for a while. Updating expected power right away keeps the estimate accurate and reduces unnecessary waiting.

Design Recipe (Generic)

1. Define your device levels from highest demand to lowest demand.
2. Assign a headroom threshold (kW) for each non-fallback level.
3. Assign expected power (W) for each level.
4. Evaluate levels top-down, then fall back to the lowest level.
5. On each level change, update expected power to the matching watts.

Example Mapping (Connected 300)

Level	Headroom Check	Expected Power
Max	3 kW	3000 W
Medium	1.75 kW	1750 W
Low	fallback	1250 W

Decision shape:

• if 3 kW fits, use Max
• else if 1.75 kW fits, use Medium
• else use Low

Quick Validation Checklist

• When headroom is low, the device goes to fallback level.
• When headroom increases, the device can step up.
• After each level change, expected power in PELS matches the new level quickly.
• No repeated "set same level" spam in the flow logic.

Common Pitfalls

• Mixing units: headroom checks are kW, expected power updates are W.
• Missing one level in the expected-power mapping.
• Using multiple unrelated flows that fight each other.
• settings.load configured for the device: manual expected-power overrides are rejected by design.

PELS Cards Used

• Is there headroom for device?
• Set expected power for device