I've started having trouble with my MM211 when using 110v. I can't weld more than 1/2 inch and the supplementary protector trips. Doesn't happen when using it on 220v. I've loosened the tension on the wire feeder and replaced the liner in the MIG gun. Any ideas what's causing this? I use this when I go onsite to install hand rails and I need to get it fixed quick. Any help appreciated.