Rockwell Automation 193/592-EC1/EC3/EC5 E3 and E3 Plus Solid-State Overload Relay - Quick Reference - Manual (Page 13)

13
Publication 193-QR003B-EN-P - October 2009
Figure 7: External CT Connection Diagrams
External Potential (Voltage) Transformer Application
(Cat. No. 193/592-EC5_ _)
The E3 Plus Overload Relay Catalog Number 193/592-EC5_ _ can be used with external
step-down potential transformers (PTs). The PT ratio is programmed into the E3 Plus by
entering the primary winding rating into Parameter 289, PT Pri, and the secondary winding
rating into Parameter 290, PT Sec. The voltage mode is also programmed into the E3 Plus by
selecting the appropriate mode in Parameter 156, Volt Mode. The E3 Plus will support Wye,
Delta, and Open Delta voltage modes with potential transformers.
IEC NEMA
L1 L2 L3 L1 L2 L3
E3 E3
M
M
K1
T1/2
T1
T2
T3
T2/4 T3/6 T
L1/1 L2/3 L3/5 L
T1/2 T2/4 T3/6
L1/1 L2/3 L3/5
Primary
Current
Transformers
Primary
Current
Transformers