Gentlemen, I would appreciate it if you could answer a couple of simple questions.
On page 3 of the Service Bulletin, what is the ID number(s) for the ACT244s?
Did pre-Rev-L TIUs use the ACT 244?
Since the surges that damage the ACT244s (unless they just "wear out") originate in derailments, would it make sense to install a heavy duty TVS in each block, near the single centerrail drop called for by DCS, to snub the surge before heading to the TIU. I do recognize that TVSs should be near to the device they protect, but seems to me that snubbing the surge can take place anywhere between origin and victim. ????
