Question 1

All registers return zero or no data after connecting. Why?

Accepted Answer

The Acti9 Smartlink acts as a concentrator: each downstream PowerTag or meter is accessed using a per-channel Modbus unit ID, not the gateway's own unit ID. Verify you are polling the correct unit ID for the specific sensor channel. The Smartlink automatically assigns unit IDs to wireless devices starting at 150 and upward; check the Smartlink web interface to confirm the assigned address.

Question 2

Phase current readings look correct but energy counters read zero.

Accepted Answer

The active_production_energy and active_consumption_energy registers are uint64 spanning four consecutive 16-bit holding registers. Some Modbus masters fail to read a 64-bit value correctly if they request fewer than four registers or apply the wrong byte order. Confirm your polling configuration requests four registers starting at address 3207 (production) or 3211 (consumption) and uses big-endian word order as documented for this device.

Question 3

The gateway connects but values disappear periodically. What is happening?

Accepted Answer

Wireless PowerTag sensors communicate to the Smartlink on a configurable reporting interval. If the Smartlink has not yet received a fresh value from a sensor when the gateway polls, it may return the last known value or a stale timestamp. Ensure the polling interval in the ModbusCloud portal is set longer than the sensor's wireless communication period, and check that the PowerTag is within wireless range of the Smartlink.

Question 4

I see unexpected values on voltage registers after changing panel wiring.

Accepted Answer

The Acti9 Smartlink must be configured with the correct phase assignment for each PowerTag sensor. If the phase selection set during commissioning does not match the actual wired phase, voltage readings on voltage_l1, voltage_l2, and voltage_l3 will be misaligned. Recommission the affected sensor through the Smartlink web interface or Ecoreach software, selecting the correct phase connection.

Name	Address	Function	Type	Unit	Access
current_l1 Phase 1 RMS current, amperes, float32.	2999	FC04	float32	A	R
current_l2 Phase 2 RMS current, amperes, float32.	3001	FC04	float32	A	R
current_l3 Phase 3 RMS current, amperes, float32.	3003	FC04	float32	A	R
voltage_l1 Phase 1 line-to-neutral voltage, volts.	3027	FC04	float32	V	R
voltage_l2 Phase 2 line-to-neutral voltage, volts.	3029	FC04	float32	V	R
voltage_l3 Phase 3 line-to-neutral voltage, volts.	3031	FC04	float32	V	R
active_power_l1 Phase 1 active power, watts, signed.	3053	FC04	float32	W	R
active_power_l2 Phase 2 active power, watts, signed.	3055	FC04	float32	W	R
active_power_l3 Phase 3 active power, watts, signed.	3057	FC04	float32	W	R
active_power Total three-phase active power, watts, signed.	3059	FC04	float32	W	R
reactive_power Total three-phase reactive power, volt-amperes reactive.	3067	FC04	float32	var	R
frequency AC supply frequency, hertz, typically 50 or 60.	3109	FC04	float32	Hz	R
active_production_energy Cumulative active energy produced, watt-hours, uint64.	3207	FC04	uint64	Wh	R
active_consumption_energy Cumulative active energy consumed, watt-hours, uint64.	3211	FC04	uint64	Wh	R

Schneider Acti9 Smartlink

Overview

Use cases

Installation

Things to watch for

Registers (14)

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