NIR use them only for shunting and permanent way work. And quite frequently to rescue the high profile "Enterprise" train run jointly between Irish Rail and NIR. The NIR units are painted in a blue livery.
The 071 class locomotives when delivered had 12-645E3s when new, however these engines were upgraded to 12-645E3Cs later, these upgrades were not carried out to the NIR locomotives or Irish Rail's 073. When new the locomotives were capable of producing 2300 b.h.p, following upgrades they could produce 2510 b.h.p.
They have a top speed of 90 m.p.h, weigh 101 tons and have a Co' Co' wheel arrangement. They are capable of multiple working and push pull.
While the bulk of the class is still at work shuttling freight around the network, #080 and #081 are out of service while their respective overhauls are underway.