Issue:
Customer would like to know when the ATV18 became obsolete.

Product line:
ATV18, Altivar 18

Environment:
All models, all serial numbers

Cause:
Determine age of unit, product obsolescence

Resolution:
ATV18 became obsolete in 1995. 
The current replacement is the ATV12, ATV312 or ATV320 depending on the application (Current, HP and Voltage of the motor). 
There are some differences in dimensions, wiring and programming that should be reviewed by the customer.