Hardware modification example - Arc protection - Auto synchronization - Bay control and measurement - Merging unit - Transformer protection - 2 winding - Feeder protection - Voltage regulation - Capacitor bank protection - Petersen Coil control - Grid automation - Busbar differential protection (high impedance) - Back-up protection - Motor protection - Busbar protection (voltage and frequency) - Transformer protection - 3 winding - Interconnection protection - Generator protection - Power management/Load shedding - Modification Sales Guideline - REX640 Protection and control - PCL5 - IEC - ANSI

Table 1. Example of the Relay module modification information table included in the relay modification delivery
Slot	Original standard case		Action	Modified standard case
Slot	Item	Description	Action	Item	Description
A1	Empty		Unchanged	Empty
A2	2RCA034483A 0901	COM1902	Unchanged	2RCA034483A 0901	COM1902
B	2RCA034506A 0901	BIO1901	Unchanged	2RCA034506A 0901	BIO1901
C	2RCA034536A 0901	BIO1902	Changed	2RCA034450A 0901	RTD1901
D	2RCA034536A 0901	BIO1902	Unchanged	2RCA034536A 0901	BIO1902
E	Empty		Added	2RCA034931A 0901	BIO1904
F	2RCA034442A 0901	AIM1901	Unchanged	2RCA034442A 0901	AIM1901
G	2RCA034455A 0901	PSM1901	Unchanged	2RCA034455A 0901	PSM1901

Explanations

Original relay columns define the slot allocation of the different modules that are included in the relay to be modified.
Action column defines the action to be done per each slot of the relay.
- Unchanged: slot is not affected by the modification
- Changed: slot content is changed by the modification, that is, to another module type
- Added: a new module is added to an empty slot by the modification
Modified relay columns define the slot allocation of the different modules after the modification is completed.