Specifications

JD and LD-Frame Trip Adjustments
11
The ground fault option has two modes of operation. The
modes are set by a switch on the side of the trip unit with the
settings identified as GROUND RETURN and RESIDUAL.
See Figure 1 for switch location.
Residual Setting (Outgoing Circuit Method)
This is the standard position to which the breaker is set when
shipped from the factory. With the switch in this position the
circuit breaker may be used on 3 phase 3 wire or, with the
addition of an external neutral sensing transformer, on 3
phase 4 wire systems. See Neutral Sensing Transformer
section pages 45 and 46 for more information.
Ground Return Setting (Ground Return Method)
This setting may only be used for service disconnects or
separately derived systems. With the switch in this position
the circuit breaker may be used on 3 phase 3 wire and 3
phase 4 wire systems. An external sensing transformer which
is installed on the main bonding jumper is required for this
method. See Neutral Sensing Transformer section pages 45
and 46 for more information.
Neutral Sensing Transformer
An external transformer is required for circuit breakers
equipped with ground fault protection when operating in the
RESIDUAL mode on 3 phase 4 wire systems and when
operating in the GROUND RETURN mode on any system.
The sensors listed below must be used for these applications.
The sensor catalog number must be matched to the circuit
breaker Maximum Continuous Current rating (In) as shown in
Table 1. Please note that sensors used with other breaker
types cannot be used with the SJD/SLD circuit breakers.
Installation instructions are included with the sensors.
Table 1
Transformer
Catalog No.
Circuit Breaker
Rating
Transformer
Color
NO2SJD200
NO3SJD300
NO4SJD400
NO5SLD500
NO6SLD600
Amps
Amps
Amps
Amps
Amps
GREEN
GREEN
GREEN
GREEN
GREEN
Electronic Testing
Sensitrip III solid state molded case circuit breakers may be
tested for electronic functionality by the use of TS-31 test set.
Maintenance
JD and LD frame circuit breakers are designed to provide
years of maintenance free service. Experience has shown
that properly applied molded case circuit breakers normally
do not require maintenance. However, some industrial users
may choose to establish an inspection and maintenance
procedure to be carried out on a regular basis. For detailed
information, consult applicable NEMA publication or your
local Siemens sales office.
NOTE: Do not spray or allow any petroleum based chemi-
cals, solvents or paints to contact the molded parts or
nameplates.