All register values read as zero even during daylight. Why?

The most common cause is an incorrect CT ratio configured on the meter. The ADW300 applies a CT multiplier to scale raw current readings. If the CT ratio is set to 1 but external CTs are in use, all derived power and energy values will be near zero. Check the CT ratio in the meter's settings menu and match it to your installed transformer ratio.

The gateway connects but no register values appear. What now?

Verify the RS485 wiring polarity: swapping the A and B terminals is the most frequent cause of a silent bus. Also confirm that the Modbus unit ID in the portal matches the address set on the meter's keypad, and that baud rate and parity settings are identical on both ends.

Phase voltage readings look wrong or wildly out of range. What should I check?

If you are using potential transformers, the PT ratio must be programmed on the meter. With direct voltage connection, the PT ratio must be set to 1. A mismatch between the configured ratio and the actual wiring produces incorrect voltage and derived power readings across all three phases.

The power register alternates between positive and negative values unexpectedly.

The power register at address 36 is a signed int32, so negative values indicate reverse power flow, which is normal when checking net-metering or grid-export conditions. If the sign is permanently inverted compared to expectation, the current transformer on one or more phases may be installed with reversed polarity. Physically reversing the CT will correct the sign.

Free Modbus template: Acrel ADW300 (pv)

Name: Acrel ADW300 (pv)
Brand: Acrel
SKU: 673e41f9-42ab-451e-b541-c976ee9f70f5

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Free Modbus template: Acrel ADW300 (pv) | ModbusCloud

Registers (11)

11 read / 0 write

Name	Address	Function	Type	Unit	Access
power Total three-phase active power, signed, in watts.	36	FC03	int32	W	R
energy Cumulative active energy imported or exported, in watt-hours.	64	FC03	int32	Wh	R
currents_a Phase A line current, unsigned, in milliamps or scaled amps.	26	FC03	uint16	mA	R
currents_b Phase B line current, unsigned, in milliamps or scaled amps.	27	FC03	uint16	mA	R
currents_c Phase C line current, unsigned, in milliamps or scaled amps.	28	FC03	uint16	mA	R
voltages_a Phase A line-to-neutral voltage, unsigned, scaled in volts.	20	FC03	uint16	V	R
voltages_b Phase B line-to-neutral voltage, unsigned, scaled in volts.	21	FC03	uint16	V	R
voltages_c Phase C line-to-neutral voltage, unsigned, scaled in volts.	22	FC03	uint16	V	R
powers_a Phase A active power contribution, signed, in watts.	30	FC03	int32	W	R
powers_b Phase B active power contribution, signed, in watts.	32	FC03	int32	W	R
powers_c Phase C active power contribution, signed, in watts.	34	FC03	int32	W	R