INSTRUKCJA OBSŁUGI

1 Purpose and Functions

The ACTii AC7392 PWM regulator with Maximum Power Point Tracking (MPPT) algorithm is an advanced microprocessor-based device designed to optimise the water heating process in standard electric DHW boilers using energy from photovoltaic panels. Solar panels reach maximum efficiency only when operating at the optimal voltage; connecting a heater directly to the panels causes excessive load, a drastic voltage drop, and a multiple reduction in generated power. The regulator eliminates this phenomenon by adjusting the load so that the system operates at the MPPT point, which allows for efficient water heating even on days with low sunlight.

The device has been equipped with an integrated charge buffer, which not only increases system efficiency by about 30%, but also significantly reduces electromagnetic interference generated by PWM regulation. Thanks to passive cooling based on a large heatsink and an intelligent temperature control system, the regulator ensures long-term and trouble-free operation without the need for noisy fans under standard conditions.

Main features:

• ✔ Advanced MPPT algorithm optimising PV panel energy intake.
• ✔ Ability to power standard electric DHW boilers.
• ✔ Precision temperature sensor with thermostat function and the ability to change the set temperature.
• ✔ Two clear LED displays providing information on temperature, current power, voltage, and peak power.
• ✔ Built-in charge buffer increasing efficiency by 30% and reducing PWM noise.
• ✔ Powered directly from PV panels (no need for external power supplies).
• ✔ Passive cooling via a large heatsink supported by thermal protection.
• ✔ RS485 communication port for monitoring operation parameters on a computer.
• ✔ Built-in acoustic alarm and housing interior temperature control.
• ✔ Potential-free relay output to notify when heating is finished or in case of failure.
• ✔ High-power reserve transistors ensuring reliability.
• ✔ Product manufactured in the European Union.

Interface and Display:

During normal operation, the regulator displays the current power and water temperature. The user can switch the view to check the panel voltage and the stored peak power. A blinking "OUT" LED indicates an active process of transferring energy to the heater.

2 Technical Specification

3 Heater Selection and System Configuration

Heater selection rules:

The regulator controls the load resistance, so both AC and DC heaters can be used. The key parameter is matching the heater resistance to the parameters of the photovoltaic panels.

It is possible to use heaters with two independent coils – one powered by PV panels through the regulator, and the second directly from the 230V grid as a backup source.

4 Operating and Programming Manual

Setting the target temperature:

1. Press and hold the MENU button until you hear an intermittent beep.
2. The message "S.tE" will appear on the upper display.
3. Use the PLUS / MINUS buttons to set the desired water temperature.
4. Confirm and exit the menu (the device will automatically save the settings).

Configuring the start voltage:

The default start voltage is 150V. To change it (recommended only when using external controller power via the RJ45 port):

• Hold the MINUS button until an intermittent signal from the buzzer appears.
• Set the new start voltage value.

Switching on and off:

• Switching off: A short press of the MINUS button cuts off the voltage to the heater.
• Switching on: A short press of the PLUS button restores automatic operation.

Note: After power loss and recovery, the regulator will automatically resume operation by default if the PV voltage exceeds the minimum value.

5 Safety and Usage Rules

Safety systems:

• Thermal protection: Automatic power limiting or shutdown after exceeding a safe temperature of the heatsink or housing interior.
• Acoustic alarm: Signalling of critical states and errors.
• Relay output: Potential-free contact informing about reaching the set temperature or actuator failure.