Throwback to the good old days !
A rusty Arakkonam (AJJ), WAM 4 6PE # 21256 waiting for starter at Chennai Egmore with 17643 Chennai Egmore - Kakinada Circar Express.
The 6P suffix...
more... indicates an arrangement of 6 traction motors in parallel while the other prevalent TM arrangement for WAM 4 was the 2S 3P configuration.
The 'E' suffix was used to differentiate locomotives equipped with air brakes only from the ones which had dual brakes (air & vacuum, DB suffix) and vacuum brakes. However, after a certain point of time owing to standardization, all WAM 4 units & other existing locomotives were configured as air brake only. Despite the standardization, sheds like Arakkonam, Vadodara & Vijaywada still continued with the 'E' suffix on their locomotives.
Circa, 2014.