Why aren't you getting full power from your charger or inverter?

An in-depth explanation of the most common causes of power losses – from cable dimension and voltage drop to battery status and temperature – as well as practical tips for optimizing your installation and achieving maximum performance.

Have you noticed that your charger or inverter isn't delivering the power stated in the specification? Or wondered why the coffee machine doesn't work while underway – even though the inverter should be able to handle it?

The explanation is simple: the temperature in the installation space directly affects the power.

Temperature's impact on power

Most specifications apply at 25 °C. But if your equipment is mounted in the engine room, the temperature while underway can be around 50 °C – and that changes everything.

Example of power loss:

• Charger: 50 A at 25 °C → 31 A at 50 °C
• Inverter: 2000 W at 25 °C → 1240 W at 50 °C (only 62% of stated power)

Even at 30 °C on a warm summer day, the difference is noticeable:

• Charger: 48 A
• Inverter: 1900 W

Three questions before sizing your electrical system

1. Where are your components installed?
2. What is the temperature range in the installation space?
3. What minimum power do you need?

How to find the right solution

Use Victron Toolkit and the Temp Derating function to simulate how temperature affects power and plan your installation accordingly.