Hello, while I’m familiar with the DL4 I have never owned one. However I’m not familiar with the PowerMax. The first thing I question is what is the voltage requirement for the DL4 (9 or 18 Volts or more)? While you could be supplying a source capable of handling the current requirements you may not be supplying the proper voltage. What is the voltage at the plug being put into the DL4? That must be correct. Sorry I couldn’t be of more help. Out of curiosity could you be more specific or provide a link to this PowerMax supply? Thanks.