If the lights are on, it would appear power is there, so fuse ok.
Is this the first charge?
My Ping battery arrived almost fully charged. I followed the instructions because it said the battery would need charging. I left it plugged in and turned on for 14 hours (just sat their doing nothing - red and green lights on ??).
Have you double-checked the wiring (just in case)?
Here's a link to a thread I did about replacing my SLA with a Ping battery (may be helpfully to you).
Dilemma with replacing my SLA batteries
If all else fails - have you considered emailing Ping to see if he can help identify the problem?
Li Ping -
pingping227@hotmail.com
.