Yes, they can be converted by repositioning jumpers on a voltage selection board. There is unsoldering/resoldering work involved. There is also a varistor across hot and neutral that needs to be swapped out for one rated at 240V, but you have the option of leaving it out. I have voltage change instructions for the CA-400/CA-300. PM me and I will send it to you. For the CA-401 instructions, you will have to contact the factory.