Don't they have a time limit?? This last few times my suit will just flash 'low energy' until I kill or get killed. The most recent I waited nearly a minute just to rule out multiple.

Yes, your suit does reboot but it takes quite a while.

How can I find out time limit on this?? It used to be 10-15 sec max.

Don't know but it if takes a nearly a a minute it maybe a bug or few of them.

Whenever I use a emp its like only a few people are affected, most of the time my emp is bugged and I can't even use it.