In the Design Estimate Tool in Designer Express, if several identical cost items are added to a DFC that is a linear feature, the quantity is not calculated correctly. In the image below, the 2/0ACSR cost item has been added to the Dx OH MV Three Phase Primary OH three times. The length of the conductor is originally 100m, so the quantity should be 300m, given that three 2/0ACSR cost items have been added. Instead, the quantity has been incremented by one, when the second and third cost items are added.
This also occurs when Palette items have been configured with multiple identical linear cost items.
This behavior is caused by bug CLS-60457, "Cost items are not summed when feature contains multiple identical linear cost items."
The work-around is to manually edit the Quantity field to set the correct quantity. This bug is fixed in the latest patch for ArcFM 10.2.1b SP1.