First of all, welcome to the forum. We're happy to have you as a member.
You didn't indicate what year your Springdale is, so some of this may not apply to you. The power center (AC distribution panel, DC distribution panel and 12 VDC converter/charger) is a WFCO 8900 series. You probably have a WFCO 8955 installed (if it's a relatively new trailer). The 8955 is composed of a 30amp "AC side" and a 55amp "DC side".
As stated, the battery may be your problem. To find out, disconnect the battery completely. If the DC works, then it's the battery, if the DC still doesn't work, you need to follow the WFCO troubleshooting steps found in the manual. You can download the WFCO support documents here:
http://wfcoelectronics.com/product/wf-8955-55-amp/
Depending on the age of your Springdale, the WFCO warranty is 2 years from date of purchase, so you may still have warranty service for the converter/power panel.
One of the most common issues is connecting the battery "backwards". There are two 40amp "reverse polarity" fuses mounted on the side of the WFCO power panel. If, even for an instant, the battery connections are "touched to the wrong battery terminals" you've likely blown those fuses causing a "no power" condition.
Download the WFCO manual, follow the troubleshooting steps and if you do need a replacement converter, it'll most likely be the 55 amp unit. It will be clearly marked, once you gain access to the back side of the power center, where the converter is mounted.
Good Luck and keep us posted on your results.