A localized ARAN VISION modernization scoping framework adapted for Iranian factories and OEMs.
Document what is installed before what you want
List the CPU, rack, modules, network, HMI, associated drives and existing program version in a table. For obsolete parts, “a Siemens or Delta replacement” is insufficient: identify required signals, protocols and allowable production downtime.
Interfaces often cost more than the CPU itself
Connections to SCADA, weighing, machine safety, servos and existing electrical panels often determine project duration. Define each interface's signal type, address and the other party's responsibilities. This avoids vague requests such as “I need a new PLC.”
Lock down acceptance criteria before coding
Specify which sequences must remain unchanged, which alarms must move to the new HMI and what FAT/SAT testing is sufficient. Without acceptance criteria, modernization becomes endless redesign and no quotation has a dependable basis.