Ok sorry to wake this thread again, but it is relevant. The lenze 534 spindle control unit went up in a puff of smoke, even after surgery by a good spirited member, it finally drew its last amp whilst re-connecting. After shedding a solo tear the knowlegable i2i pointed me in the direction of Sprint Electric Sprint Electric - DC Motor Control Technology after a few emails to the Helpfull engineers there, I arrived at the 1220 1Q 12.2A 1.8kW, 2Hp @180V Unit. It sat in the workshop for 2 months. Today i got the Lenze 534 manual and the Sprint 1220 manual and swapped the wires over and after a little tweeking like magic the old girl wizzed out 4500 rpm no probs. So there you have it.. Lenze 534 dead?? get over to those nice chaps at Sprint..

Rick