I think that in-line fuse is a 30Amp fast blow.
One nice thing about having multiple UPS's is that if one dies, you've not lost your entire system.
I have four of them. Plus a 1800W inverter connected to TWO HUGE deep cycle batteries, that I use to power up my Kitchen Appliances when there is an Area Wide power failure.
I can recharge any of my batteries off of my car, with jumper cables. I did that for five days, during Hurricane Frances, when we had NO line power at all.
I had TV, light, a personal fan and all my kitchen appliances, while the neighbors sat in the dark.
Portable power! (1800W inverter and two Deep Cycle batteries, on a mover's dolly, so I can move it anywhere in the house)