What you need to worry about, is whether the gauge of the new wire is heavy enough to carry the needed power to the buckets without overloading. Having all those quantity of bucket outlets on one circuit CAN overload even heavy wiring.
Wire being new has nothing to do with what power load it can carry if wires are a small guage, easy to overload. Kind of like tank heaters, which draw BIG amounts of electric power. If the wire to the outlet is not heavy enough, the heater doesnât get the needed power to heat the water. Heater will have a short life, die, and probably you tank will not stay unfrozen in real cold either. One friend complaining about âcrappy heatersâ since she bought new each year, told us how she had things rigged. The run to the tank was almost 500 ft of medium gauge 14 wire. We told her she was lucky the heater worked at all, with that tiny bit of power reaching it!! The smaller the number gauge of wire, 12-10, means the bigger the wire inside the plastic cover. Big wires are easier to carry power loads with, take big power draws at the plug-in point.
Normal 14-16 guage electric cords fail on longer runs, with heavy power use items, burn out the heater, buckets, with their failure to carry lots of power to the appliance. Those are fire hazards. Cords run to plug things in can leak electric thru the plastic covers, get water in the plugs to fail by shorting out.
If your Dad wired the barn, go talk to him. Ask about wire gauge he used. Get the specs of power needed by the heated buckets. Length of wire runs to the stalls they will be used in, which could cause dropping in power feed if long enough. If Dad is just a good wirer, perhaps calling a licensed Electrician to answer your questions, pay his fee to visit and inspect wiriing, would settle your mind about heated bucket use. Electrician is tested on this knowledge, should be able to help you out best.