A Dangerous Legacy of old Bell Telephone Transformers

At left is 2 pictures of a Plug in transformer that was used in many commercial buildings to supply power  for telephone functions a smaller version was used in homes to light up the dial on rotary  princess phones which you often found in a homes bedroom which allowed you to answer the phone and dial in the dark.
The phone had a 4 wire instead of traditional 2 wire connection  the red and green pair provided dial tone while the yellow black was used to run the ac power to the phone to light the dial. Later phone versions used the phone line power but where not as bright.

The problem with these little transformers all over the place is they are now going on over 50 years old still plugged in drawing a small amount of power and in some cases  the transformers are deteriorating and causing problems which include shock and fire. In one case in a residence which had metal mesh under its plaster a transformer went bad and sent electrical current all over the house and was giving people shocks any time they touched metal.had I not caught the problem and corrected it eventually there would have been a fire. Now you would think ma bell would start hunting all these transformers power supply s etc down and start removing them due to all the potential problems and liabilities but that will never happen . with all the mergers, bankruptcy's etc. there is no company to hold responsible . So that leaves it up to you the property owner  and me the electrician to find and eliminate them before they become a problem.  Do not ever expect any agency to ever come out with a warning either this problem has been known for at least 25 years and no body has done any thing about it. not even the insurance company's who are very aware these transformers are causing problems. So you the consumer get screwed again. By greed.