Solar Guide
What Size Victron MPPT Do I Need?
Choose the correct MPPT solar controller for your panel size.
Quick Rule
Choose MPPT amperage = (Total Solar Watts ÷ Lowest Panel Voltage) × 1.25
For most campervans: 100/30 or 150/35 is perfect.
Victron SmartSolar MPPT Options
MPPT 100/20
Up to 150W
20A
£100-120
MPPT 100/30
Up to 200W
30A
£150-200
MPPT 150/35
Up to 300W
35A
£200-250
MPPT 150/45
Up to 400W
45A
£250-300
MPPT 150/60
Up to 500W+
60A
£300-400
Example Calculations
Example 1: 200W Solar Panel (48V)
200W ÷ 48V × 1.25 = 5.2A
✓ Choose: MPPT 100/20 (cheapest, sufficient)
Example 2: 400W Solar Panel (48V)
400W ÷ 48V × 1.25 = 10.4A
✓ Choose: MPPT 100/30 (standard campervan size)
For Campervans: Go with 100/30
The SmartSolar MPPT 100/30 is the industry standard for campervans because:
- Perfect for 200-400W solar systems
- Balanced price and capability
- Handles 48V panels efficiently
- Integrates with Victron ecosystems
- Room to upgrade panels later
Don't Undersize
⚠️ Wrong sizing = lost charging capacity
If you have 400W of panels but only a 20A MPPT, you're wasting 200W of charging power on sunny days.
Our Recommendation
All our complete kits include the correct MPPT for your solar panel size. We handle the calculations so you don't have to.