25
Instructional Leaflet
IB2C12063H03
Effective March 2012
Instructions for Installation, Operation and
Maintenance of Magnum SB Insulated Case
Low Voltage Power Circuit Breakers
EATON CORPORATION
www.eaton.com
Figure 33. Pictorial Diagram of Typical Current Sensing, Processing and Tripping System
The electronic trip units are self-powered . When the circuit
breaker is closed, no external power is required to operate their
protective systems . Current signal levels and the control power
are derived from the current sensors integrally mounted in the
circuit breaker .
A functional local test of a major portion of the trip unit’s
electronic circuitry and the circuit breaker’s mechanical tripping
action can be verified through the trip unit’s test receptacle
(
Figure 34
) . This is accomplished using a Digitrip (DS Type) Test
Kit which provides a secondary injection test that simulates
the current sensors . A small hand held Magnum functional Test
Kit can also be used to check circuitry and mechanical tripping
functions (
Figure 35
) .
When the circuit breaker is shipped from the factory, the trip
unit’s protective functions are normally set at minimum values .
For specific overload tripping characteristics and time/current
curves to coordinate with a load or system, refer to the trip unit
instruction book .
Table 5. Magnum Digitrip Trip Units
Functions
520
520M
m
520MC
m
1150
m
LSIG Protection
Yes
Yes
Yes
Yes
Disable (I)
Yes
Yes
Yes
Yes
GF Protection
Yes
Yes
Yes
Yes
GF Alarm
No
Yes
Yes
Yes
Display
No
Yes
j
Yes
j
Yes
k
Programmable
No
No
No
Yes
Metering
No
Yes
l
Yes
l
Yes
Power and Energy Values
No
No
No
Yes
Power Quality
No
No
No
Yes
Communication
No
No
Yes
Yes
j
One-line, (four characters per line) LCD display.
k
Three-line, (eight characters per line) LED display.
l
Phase, neutral, ground, and high load current only.
m
Available control voltages are 24/48Vdc, 125Vdc, 120Vac and 240Vac
