A good bear fence keeps them out.
A crappy bear fence educates them and is expensive.
1. Get a good charger such as parmak magnum ( battery operated) or equivalent. You want 7 to 8,000 volts, minimum on fence.
2. Get a decent battery such as a small deep cycle. We use 35 amp hour DC battery (SigmasTek brand). Small lawn tractor batteries do not last long. Auto or marine deep cycle work but are a bit bulky for transporting to various bee yards.
3. To keep battery charged we use 20 watt solar panel and run it thru a small charge controller ( Instapark waterproof 5 amp charge controller). 20 watt solar panel is at 3 to 4 times the wattage found on all in one solar fence chargers.
4. Run 5 wires, top- middle- bottom hot, the other two to ground.
5. Use at least 2 ground rods, one at charger and one at farthest point from charger.
6. Space wires about 8” apart.
7. Get a fence tester with voltage readout. Less than 7k correct problem.
8. We set up empty hive inside the fence and put charger, battery inside and solar panel on top.
9. I like the lockjawz snap on t-post insulators, order direct from manufacturer. One style insulator use it for corners, straight runs and terminations.
10. Spring tensioners and fence accessories we get from Kencove fencing.
11. For temporary fence you can get by with 17 gauge wire but we build with 14 gauge wire. Not a whole lot more cost but lasts a lot longer. No need for the extra expense of aluminum wire.
You will invest about $250-300 in a good fence system. Less than the value of a strong hive with harvestable honey on it.