Deye system work modes explained

The System Work Mode menu is the brain of a Deye hybrid — it decides how solar, battery and grid feed the loads, and whether the system is allowed to export. You pick one base mode, then set a few toggles and limits. For a typical Australian install the answer is Zero Export to CT, but here’s what each option actually does.

The three work modes (pick one)

Selling First — export the excess

The inverter sells any excess solar back to the grid. With Time-of-Use active, stored battery energy can be sold too. Solar powers the loads and charges the battery first; whatever’s left flows to the grid.

• Load power-source priority: ① solar → ② grid → ③ battery (down to your set discharge %).
• It’s a generation-limit mode: Max Sell Power is the soft cap on what the inverter exports; Zero-export Power is the hard cap.
• Use it where the network allows export and the customer wants to maximise feed-in.

Zero Export to Load — backup-focused

The inverter powers only the backup loads on its backup/EPS port, not the home (on-grid) loads. Its built-in CT watches for power heading back to the grid and throttles the inverter so it supplies the local load and charges the battery. It won’t export by default — but you can turn on Solar Sell in this mode to let surplus solar feed the grid.

• Narrow use case: backup-load-only, with optional surplus export via Solar Sell.

This setting limits what the inverter supplies (backup-load port only, and no export unless Solar Sell is on). It does not stop the grid from supplementing the loads or charging the battery — that is governed by the Energy Pattern and grid-charge settings, not by the work mode.

Zero Export to CT — no export, whole-home ✅ usual AU choice

The inverter powers the backup loads and the home loads. If solar + battery can’t cover the load, it tops up from the grid — but it never exports. An external CT on the main incomer detects any back-feed and reduces inverter output to match local demand plus battery charging.

• This is the mode most AU installs run (zero-export network conditions), and the base mode the Time-of-Use guide layers on top of.
• It relies on the external CT being wired the right way — see Smart meter wiring.

Mode	Backup loads	Home loads	Exports to grid	Sensing
Selling First	✓	✓	✓ (excess)	generation limit
Zero Export to Load	✓	✗	✗ (unless Solar Sell)	built-in CT
Zero Export to CT	✓	✓	✗ (unless Solar Sell)	external CT on main incomer

The zero-export (export-limit) modes only work with a CT or meter installed. With no CT/meter the inverter can’t measure back-feed, so it can’t guarantee zero export.

The toggles and limits

• Solar Sell — the exception switch for the zero-export modes. Turn it on and surplus solar may be exported even in Zero Export to CT/Load. PV then flows loads → battery → grid. Leave it off for true zero export.
• Max Sell Power — the ceiling on power allowed out to the grid (the soft export limit).
• Zero-export Power — the hard limit for zero-export mode. Set it to 20–100 W — a small margin that guarantees the inverter never actually feeds the grid.
• Energy Pattern (PV priority):
  • Batt First — solar charges the battery first, then powers the load. If PV is short, the grid supplements both battery and load.
  • Load First — solar powers the load first, then charges the battery. If PV is short, the grid supplements both.
• Grid Peak-shaving — caps how much power is drawn from the grid. If the load exceeds the set value, PV + battery make up the difference; only if they still can’t cover it does grid draw rise to meet demand. Useful where the site has a demand/import limit.

A sensible AU default

For a standard zero-export residential install:

1. Work mode: Zero Export to CT
2. Solar Sell: on if the network allows any feed-in, off for hard zero export
3. Zero-export Power: 20–100 W
4. Energy Pattern: Load First for self-consumption (or Batt First if the priority is filling the battery for backup / peak cover)
5. Layer Time-of-Use on top to schedule off-peak charging — see Set up Time-of-Use.

From the System Work Mode Setup Menu (§5.7) of the Deye hybrid manual. Exact labels and available options vary by model and firmware — always confirm against the unit in front of you.