[Carl n Susan]

Color me confused! There are two distinct and separate systems being referenced.

Hydraulic Slides - The hydraulic slide system power goes from the battery through a 30 (or 40 - it depends) Amp self resetting circuit breaker.

Jacks - The landing leg jacks are electric all the way (no hydraulics unless you have the Lippert 6 Point Leveling System which was not available originally for a 2980) with power from the battery flowing through an in-line 30 Amp blade type fuse.

Operating the slides will not affect the 30 Amp blade fuse for the jacks and vice versa.

The OP reports changing the fuse each time it blows. This implies (at least to me) it is the 30 Amp in-line blade fuse for the landing legs. Increasing the size to 40 Amp is the normal solution for this problem. But blowing the fuse is usually due to extending/retracting too far or indicative of leg problems (bent, not lubricated, etc.). A 2980 doesn't have enough weight on the front jacks (unlike some other models) to overload the capacity of the jacks.

The 30 (or 40) Amp self resetting circuit breaker for the hydraulic slides is a much more common problem. And the CB gets a little weaker each time it "pops" making it more prone to "popping" during subsequent usage. While it "fixes itself" without human intervention, the starting/stopping is irritating. The solution here is to upgrade to an 80 Amp CB or wire two 40 Amp CBs in parallel.

A "Search" on either of these terms should uncover a number of examples on the corrections.