The gateway connects but all register values read as zero.

The AcThor9s only exposes Modbus TCP register data when its control type is explicitly set to 'Modbus TCP' in the device settings. If another control mode such as 'Adjustable Modbus TCP' or a direct inverter integration is active, the device will not serve holding register reads. Switch the control type to 'Modbus TCP' and retry.

Register reads fail intermittently or the connection drops frequently.

The AcThor9s manages only one active Modbus TCP client connection at a time. If another system such as a home automation controller or energy management system is also polling the device, connections will be rejected or interrupted. Ensure only the ModbusCloud Gateway is connected to port 502 during monitoring.

Voltage or current values look correct but active_power reads unexpectedly.

The AcThor9s documentation notes that some Modbus clients must add 1 to the real register address. If your portal or gateway applies a register offset, address 1000 may be polled as 1001, causing misaligned reads. Confirm the ModbusCloud template uses real addresses without an offset, which is the correct configuration for this device.

The status register shows a value of 200 or higher. What does that mean?

Status codes of 200 and above indicate power-stage error conditions on the AcThor9s. Status 9 is normal operation, codes 1 through 8 indicate the device is still starting up. An error-range status typically requires a power cycle of the unit and, if the fault persists, a firmware check or contact with MyPv support.

Free Modbus template: MyPv AcThor9s

The MyPv AcThor9s is a three-phase PV power diverter that routes surplus solar energy into electrical heat sources such as immersion heaters and space heating elements, with linear power control from 0 to 9 kW across up to three outputs. This Modbus TCP template reads total active power, per-phase voltage and current, per-phase active power, sensor temperature, and device status. Together these registers let you track exactly how much solar surplus the AcThor9s is consuming, verify load balance across all three phases, and confirm the device is in normal operation rather than a fault state.

Name	Address	Function	Type	Unit	Access
active_power Total active power currently consumed by the heating element, in watts.	1000	FC03	int16	W	R
temperature Temperature reading from the primary connected sensor, in degrees Celsius.	1001	FC03	int16	°C	R
voltage_l1 AC voltage on phase L1, in volts.	1061	FC03	int16	V	R
current_l1 AC current on phase L1, in amperes.	1062	FC03	int16	A	R
voltage_l2 AC voltage on phase L2, in volts.	1067	FC03	int16	V	R
current_l2 AC current on phase L2, in amperes.	1068	FC03	int16	A	R
voltage_l3 AC voltage on phase L3, in volts.	1072	FC03	int16	V	R
current_l3 AC current on phase L3, in amperes.	1073	FC03	int16	A	R
active_power_l1 Active power delivered on phase L1, in watts.	1074	FC03	int16	W	R
active_power_l2 Active power delivered on phase L2, in watts.	1075	FC03	int16	W	R
active_power_l3 Active power delivered on phase L3, in watts.	1076	FC03	int16	W	R
status Device operating status code: 0 off, 1-8 start-up, 9 operating, 200+ error.	1077	FC03	int16		R