Instructions for Digitrip RMS
310
Trip Unit For Use with
R-Frame Breakers
TABLE
OF
CONTENTS
Description
Page
1.0
General Information..
. . . . . . . . . . . . . . . . . . . . .
1
1.1
Protection..
. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1
1.2
Testing..
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.0
UL Listed Devices
. . . . . . . . . . . . . . . . . . . . . . .
3.0
Principle of Operation.
. . . . . . . . . . . . . . . . . . . . .
2
3.1
General..
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.2
. . . . . . . . . . . . . . . . . . . . . . . . . . . .
2
3.3
Short
Trip
. . . . . . . . . . . . . .
2
3.4
Ground Fault Protection.
. . . . . . . . . . . . . . . . . . .
3
4.0
Protection Settings
. . . . . . . . . . . . . . . . . . . . . . .
3
4.1
General
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3
4.2
Short Delay Pick-up Settings
. . . . . . . . . . . . . . . .
3
4.3
Short Delay Time Settings
. . . . . . . . . . . . . . . . . .
3
4.4
Instantaneous Pick-up
. . . . . . . . . . . . . . . . . . . . .
3
4.5
Ground Fault Pick-up Setting
. . . . . . . . . . . . . . .
3
4.6
Ground Fault Time Setting
. . . . . . . . . . . . . . . . .
3
6.0
Frame Ratings and Ratings Plugs
. . . . . . . . . . . .
5
7.0
Reference..
. . . . . . . . . . . . . . . . . . . . . . . . . . . .
7.1
Digitrip RMS Trip Assemblies.
. . . . . . . . . . . . . . .
5
7.2 R-Frame Molded Case Circuit
Breakers
. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.0
Testing
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
WARNING
DO NOT
TO INSTALL
OR
PERFORM MAIN-
TENANCE ON EQUIPMENT WHILE IT
IS
ENERGIZED.
DEATH, SEVERE PERSONAL INJURY,
OR
SUBSTAN-
TIAL PROPERTY DAMAGE CAN RESULT FROM CON-
TACT WITH ENERGIZED EQUIPMENT. ALWAYS
VERIFY THAT NO VOLTAGE
IS
PRESENT BEFORE
PROCEEDING WITH THE TASK, AND ALWAYS FOL-
LOW GENERALLY ACCEPTED SAFETY PROCE-
DURES.
THE CUTLER-HAMMER
IS NOT LIABLE
OF ITS PRODUCTS.
The user is cautioned to observe all recommendations,
warnings, and cautions relating to the safety of personnel
and equipment as well as all general and local health and
safety laws, codes, and procedures.
FOR THE MISAPPLICATION
OR MISINSTALLATION
The recommendations and information contained herein
are based on Cutler-Hammer experience and judgement,
but should not be considered to be
or cover-
ing every application or circumstance which may arise. If
any questions arise, contact Cutler-Hammer for further
information or instructions.
1
GENERAL INFORMATION
1.1
Protection
The Digitrip
RMS 31
0,
illustrated in Figure 1, is an elec-
tronic trip unit that incorporates a microprocessor-based
custom application specific integrated circuit design for
use with R-Frame Molded Case Circuit Breakers.
Fig.
1
Digitrip RMS
310
Unit for use with R-Frame
Circuit Breakers
The Digitrip
RMS 310 provides true RMS current sensing
for proper correlation with thermal characteristics of con-
ductors and equipment. Interchangeable rating plugs are
provided to establish the continuous current rating of
each circuit breaker.
Effective
February 2006 Supersedes I.L. 29C883C dated July 2003
I.L. 29C883E
