Reversing the wire through the sensor took care of that problem. As I think about it, the drawing showed the negative cable, and I used the positive, so I should have reversed it. Thank you all.
Now, a couple of follow up questions. Can the meter panel be switched to black vs white? I can't find any way to do it. The pictures of the unit I bought showed both on the Ebay site. It isn't a big deal, but the panel is bright, and I'll probably have to cover it if we have someone sleep on the hide-a-bed in the living area.
I understand the voltage, current and remaining capacity readings. Are the other details worth bothering with?
Thanks again for all of the help.