Enclosed Variable Transformer. Professional range of enclosed variable transformers available in either single or three phase. The transformers are not designed to provide mains isolation but do operate at mains voltage. All of the transformers need to be earthed using the earth studs provided. A robust range of enclosed style variable transformers for surface floor or wall mounting Single or three phase versions available in a range of current ratings Continuously variable AC output voltage with overvoltage tap Heavy duty construction High efficiency ; excellent regulation No wave form distortion Silver plated commutator Over-load capacity Smooth linear output Negligible maintenance Trouble free long life