Rockwell Automation 193/592-EC1/EC3/EC5 E3 and E3 Plus Solid-State Overload Relay - Quick Reference - Manual (Page 15)

15
Publication 193-QR003B-EN-P - October 2009
External Ground Fault Sensor Application
(Cat. Nos. 193/592-EC3_ _, 193/592-EC4_ _, and 193/592-EC5_ _)
Cat. Nos. 193/592-EC3 _ _, 193/592-EC4 _ _, and 193/592-EC5 _ _ E3 Plus Overload Relays
are intended to provide ground fault protection when used with the cat. no. 193-CBCT _
external ground fault (core balance) sensor. The ground fault sensor mounts separately from
the E3 Plus Overload Relay and must be placed within three meters of the relay. The
customer-supplied cable for wiring the ground fault sensor to the E3 Plus Overload Relay
should meet the specifications outlined in Table 1.9 on page 15.
Power Cable Installation Instructions
1. All power cables (including the neutral when used) must pass through the sensor
window. The equipment ground conductor (the conductor used to carry the
non-current-carrying metal parts of equipment, as defined by Article 100 of the
NEC), must not pass through the sensor window.
2. The power cables through the sensor window should be straight, tightly bundled,
centered in the window, and perpendicular to the sensor for a length equal to, or
greater than, six times the cable diameter (including insulation) from the sensor.
3. All other conductors with available currents in excess of 1,000 A should be placed a
distance equal to, or greater than, six times the cable diameter (including insulation)
from the sensor.
4. The power cables of the branch circuit to be protected by the E3 Plus Overload Relay
must not be grounded on the load side of the ground fault sensor.
5. If the power cables are enclosed in a conducting jacket, the jacket must be grounded
on the line side of the sensor. The jacket must not pass through the sensor window,
but must be cut at the window and joined with a conductor that passes outside the
sensor window.
6. The power system may be solidly grounded or grounded through an impedance at its
source as long as the impedance allows a magnitude of fault current to flow that is
within the 1…5 A operational range of the E3 Plus Overload Relay (193/592-EC2_
_) or the 20 mA…5 A operational range of the E3 Plus Overload Relay (193/
592-EC3
_ _, 193/592-EC4 _ _, and 193/592-EC5 _ _ ).
Table 1.9 Ground Fault Sensor Terminals (S1 and S2)
Wire type Shielded, twisted pair
Cross section 0.2…4.0 mm 2 (#24…12 AWG)
Torque 0.55 N • m (5 lb-in.)