Can I use 9V 800mA transformer to power arduino

Can i use 9V 800mA transformer to power arduino

To the best of my knowledge, no. I am not an Arduino expert, but I believe you can power your Arduino either from a 5 V USB supply, or a direct current supply of between 9 V and 12 V.

A transformer gives a alternating voltage which is not suitable.

Is this question related to the OpenEVSE?