Electrical fires almost always occur at the junctions .
The heat generated by a poor connection is what does it .
Your connection would be out in the open and you can tell by feeling if the extra connection is not a tight fit .
A 30 amp cord requires # 10 guage wire .
That cord is the larger diameter just like the pigtail coming from your trailer .
Because # 10 guage 30 amp cable is so much more expensive and wieldy some try to extend their run with the more common 14 guage or 12 guage cord .
The problem is that at higher amperage flows the smallest diameter cord restricts the overall current flow .
The best solution is probably using only # 10 guage even if you have an extra junction .
Of course a single # 10 guage say 50 feet long would be the best solution .
