DC 12V Low Voltage Protection Kit – Power and Battery Protection

Please note: this is a KIT, so you will receive the components you need to assemble and everything you need to recreate the device as shown in the image. The KIT includes easy-to-understand illustrated instructions in Italian.

REQUIRED EXPERIENCE LEVEL: medium-low

Assembly and testing by Mectronica STORE is also available by adding quantity 10 of the KIT assembly service (search for it on the site) and adding it to the cart together with the KIT to be assembled.

The Low Voltage Protection Kit is an electronic circuit designed to protect batteries and systems powered by direct voltage, typically 12 V DC , from deep discharges and voltage drops that can damage both the batteries themselves and the connected devices.

The device continuously monitors the supply voltage and, when it drops below a preset value, automatically disconnects the load , protecting the battery from excessive discharge and ensuring that the equipment only operates when the voltage is sufficient for proper operation.

The intervention threshold is adjustable via a trimmer , allowing you to adapt the protection point to the specific needs of the system or battery in use. The kit also features LED indicators that allow you to monitor the operating status and protection condition.

This kit is ideal for automotive, recreational vehicle, or off-grid applications, as well as for DIY projects, power panels, charging stations, or electronics installations where it is essential to prevent a battery from over-discharging.

Main features

• Continuous monitoring of DC voltage

• Automatic intervention for low voltage protection

• Adjustable intervention threshold

• LED indicators for operating status

• Protects batteries and loads from deep discharges

• Facilitates the management of 12V DC systems

• Easy installation even in DIY kits

• Ideal for automotive, marine, camper and electrical panel use

Typical applications

• Battery protection in 12 V DC systems

• Battery power systems

• Automotive, campers, caravans and nautical

• Control panel for electronic devices

• DIY projects and electronic prototypes

• Off-grid systems with rechargeable batteries

Load protection based on the dual LM358 operational amplifier. Applied to a DC circuit, it disconnects the load via a relay (normally energized) when the supply voltage drops below a certain value (adjustable via a dedicated trimmer). In circuits powered by traditional power supplies, the protection prevents damage caused, for example, by a power supply overload (identified by an excessive drop in the supplied voltage...) but also by the user's malfunction, which could occur precisely if the supply voltage drops excessively.

In battery-powered circuits, protection serves both to block the operation of circuits that do not guarantee correct operation at too low a voltage, and to prevent excessive discharge of the battery, to avoid damaging it or to leave the little remaining energy available for other hierarchically more important circuits.

The choice to power the user circuit with an active relay when the voltage is OK and to disconnect it otherwise arises from one consideration: if the load is powered by the battery, it is clear that the relay must be de-energized when the battery is discharging, otherwise it would discharge it further and at a certain point the relay would drop, reconnecting the load, with the consequence that this would cause a further discharge.

Technical features

• Power supply voltage: 12 Vdc
• Max switching voltage: 125 Vac
• Current consumption: 40 mA
• Intervention threshold: 0÷12 Vdc
• Switching current: 3 A
• Monitorable voltage: 0÷12 Vdc
• Dimensions (mm): 42x36x22