Context: Operating at normal power line frequencies, universal motors are often found in a range less than 1000 watts. Universal motors also formed the basis of the traditional railway traction motor in electric railways. In this application, the use of AC to power a motor originally designed to run on DC would lead to efficiency losses due to eddy current heating of their magnetic components, particularly the motor field pole-pieces that, for DC, would have used solid (un-laminated) iron and they are now rarely used.

Question: What is the typical maximum range of universal motors?
Answer: 1000 watts

Question: What type of motor was used in trailway traction applications?
Answer: universal

Question: What is the result of using AC power on a DC motor?
Answer: efficiency losses

Question: What were universal motor pole pieces constructed from?
Answer: solid (un-laminated) iron

Question: What is the atypical maximum range of universal motors?
Answer: Unanswerable

Question:  What type of motor was not used in trailway traction applications?
Answer: Unanswerable

Question: What is the result of using DC power on a DC motor?
Answer: Unanswerable

Question: What weren't universal motor pole pieces constructed from?
Answer: Unanswerable