Dear Steve, Cat and afr:

Thanks for taking the time to respond. Here are some additional details:

All trips occurred on the utility side. ATS is a 3 pole and no i did not disconnect the bonding jumper. Although, i can't imagine this would cause tripping. All neutrals and grounds were transferred individually from the Main panel into the ATS. Although,I have to admit I don't really know what a floating neutral is. Could someone expound?