Scenario - Free Freight when the weight ordered is greater than (or equal to) 100 lbs.

First, define a Freight Promotion. In this case we have defined the promotion to accumulate the order regardless of ship to.  That means that in this scenario if there are multiple ship to's on the order that will not impact how the quantity on the order is summed when considered for free freight.

Next, go to Discount Details and choose Weight. Now, configure the discount as follows:

From level - enter 100 so that when the sum weight of items on the order totals 100lbs or more this line will apply.

Factor Value - when using a quantity calculation this number will be positive.  In our example 100.

Percent or Amount - enter 0 for percent. This means that when combined with the factor value the discount will be 100% of the freight charge.

Cur Code - in our example USD

Now, associate this freight promotion to a marketing code/campaign (PQ674204) so that it can be redeemed on an order.

Finally, verify that the freight promotion works as desired.

Below you can see that the weight on the order does not equal or exceed 100lbs so the freight is not free.

However, when the order weight is equal to or exceeds 100lbs the freight promotion applies and the freight is free.