Yes, in most cases. A CT (current transformer) clamp measures the current flowing into your home or from your solar panels. Without it, the charger still charges at its fixed maximum current. What you lose are features that depend on that measurement: dynamic load balancing, solar surplus charging and some energy reports. In homes with limited supply capacity, an installer may treat the CT clamp as essential to avoid overloading the main fuse.
What a CT Clamp Enables
| Feature | Needs CT clamp? |
|---|---|
| Basic charging at a set current | No |
| Dynamic load balancing with the house | Yes |
| Solar surplus (“eco”) charging | Yes, usually on the grid and/or solar feed |
| Whole-home energy reports | Yes |
See does load balancing increase charging speed and dynamic load balancing.
Common Problems
- Clamp on the wrong cable or facing the wrong way: readings are wrong, charging may stop or never throttle.
- Wireless CT link lost: some chargers fall back to a safe low current.
- Clamp removed after rewiring: load balancing silently stops.
Hardware
Wallboxes with load management, such as the EVDANCE EV-ACT3204E 22 kW wallbox, use a CT sensor for balancing. Simple chargers like the EVDANCE EV-ACS3210T 32A NACS portable charger use a fixed, adjustable current instead, which you set to suit the circuit.
Frequently Asked Questions
What happens if my CT clamp is disconnected?
The charger usually charges at a fixed or reduced current and loses load balancing.
Do I need a CT clamp for solar charging?
Yes, for most solar surplus modes.
Can a CT clamp be installed later?
Usually yes, by an electrician.
Related Reading
Key Takeaways
- Chargers work without a CT clamp at a fixed current.
- Load balancing and solar modes need it.
- Wrong clamp placement causes odd behaviour.