I.L. 29C508B
Effective September, 2000, Supersedes I.L. 29C508A dated February 1999.
Cutler-Hammer
Installation Instructions for the Digitrip OPTIM 550 3-Pole
Trip Unit Installation and Operation with L-Frame Series C
Circuit Breakers
Table of Contents
Description
Page
1.0
General Information . . . . . . . . . . . . . . . . . . . . . .1
2.0
UL Listed Devices . . . . . . . . . . . . . . . . . . . . . . . .2
3.0
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
4.0
Principle of Operation . . . . . . . . . . . . . . . . . . . . .5
4.1
General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
4.2
Overload Trip . . . . . . . . . . . . . . . . . . . . . . . . . . .6
5.0
Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
5.1
Functional Field Testing . . . . . . . . . . . . . . . . . . .6
5.2
Performance Testing for Ground
Fault Trip Units . . . . . . . . . . . . . . . . . . . . . . . . . .6
5.2.1 Code Requirements . . . . . . . . . . . . . . . . . . . . . .6
5.2.2 Standards Requirements . . . . . . . . . . . . . . . . . .6
5.2.3 General Test Instructions . . . . . . . . . . . . . . . . . .6
6.0
Rating Plug . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
7.0
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
7.1
Series C L-Frame Molded Case
Circuit Breakers . . . . . . . . . . . . . . . . . . . . . . . . .8
7.2
Internal Accessories . . . . . . . . . . . . . . . . . . . . . .8
DEATH, SEVERE PERSONAL INJURY, OR SUB-
STANTIAL PROPERTY DAMAGE CAN RESULT
FROM CONTACT WITH ENERGIZED EQUIPMENT.
DO NOT ATTEMPT TO INSTALL OR PERFORM
MAINTENANCE ON EQUIPMENT WHILE IT IS ENER-
GIZED. ALWAYS VERIFY THAT NO VOLTAGE IS
PRESENT BEFORE PROCEEDING WITH THE TASK,
ALWAYS FOLLOW GENERALLY ACCEPTED SAFE-
TY PROCEDURES.
CUTLER-HAMMER IS NOT LIABLE FOR THE MISAP-
PLICATION OR MISINSTALLATION OF ITS PROD-
UCTS.
The user is cautioned to observe all recommendations,
warnings, and cautions relating to the safety of person-
nel and equipment as well as all general and local
health and safety laws, codes, and procedures.
!
WARNING
The recommendations and information contained herein
are based on Cutler-Hammer experience and judge-
ment, but should not be considered to be all-inclusive or
covering every application or circumstance which may
arise. If any questions arise, contact Cutler-Hammer for
further information or instructions.
1.0 GENERAL INFORMATION
The Digitrip OPTIM 550, illustrated in Figure 1-1, is an
electronic trip unit that incorporates a microprocessor-
based custom application specific integrated circuit
design for use with the Series C L-Frame Molded Case
Circuit Breakers.
The Digitrip OPTIM 550 provides true RMS current
sensing for proper correlation with thermal characteris-
tics of conductors and equipment. Interchangeable rat-
ing plugs are provided to establish the continuous cur-
rent rating of each circuit breaker.
Figure 1-1 Digitrip OPTIM 550 Trip Unit for 3-Pole
L-Frame Series C Circuit Breaker
