Magnum Ds - Current Limiting Circuit Breakers - Eaton Magnum SB Series Technical Product Manual

Magnum DS - Current limiting
circuit breakers
MDSL circuit breaker
Magnum MDSL current limiting power circuit breakers utilize
integral current limiters to provide interruption ratings of 200
kA at 600 Vac with continuous limitation with lower let through
currents for superior protection of downstream equipment .
The MDSL breaker is available only in a drawout configuration .
Current limiters are held in place in a 6 inch (152 .4 mm) extension
provided on the back of the circuit breaker . The current limiters
can only be removed from the breaker and replaced when the
MDSL breaker is removed from its associated compartment .
A blown limiter indicator provides a visual indication on the front
of the MDSL when a current limiter in any phase has interrupted
a short circuit . The indicator itself is a red pop-out button located
on the lower left portion of the breaker's front cover .
The direct trip actuator trips the circuit breaker, and an output to
the indicator causes the button to pop out .
Current limiter selection
Current limiters can be selected from the current limiter selection
table (Table 7) and are categorized for selection in three ways:
Minimum current limiter
•
Recommended current limiter
•
Maximum current limiter
•
The selection of a suitable limiter rating for a given application
is generally governed by a choice of the following two types of
protection:
(A) Maximum protection of downstream components:
Type MDSL breakers are often used for this purpose even when
the maximum available fault currents are within the interruption
rating of the corresponding unfused Magnum breakers .
(B) Protection of circuit breaker only:
Case A would tend to use the smallest available limiter; Case B
the largest .
Table 7 . Magnum MDSL sensor/rating plug vs . Current limiter selection
Sensor and
Rating plug i MDSl current limiter selection chart
n
200 MA250 MA300
250
300
400
600
800
1000
1200
1600
2000
Select the current limiter based on the Magnum breaker frame and current sensor and rating plug as shown .
1
Refer to MDSL current limiter curves for let-through and time characteristics .
2
The recommended ratings provide for reduced current let-through and breaker coordination within the trip unit settings . Selection of current limiters
3
below the recommended ratings shown provides lower current let-through, however, trip unit settings must be considered to avoid nuisance
operation .
Courtesy of NationalSwitchgear.com
Magnum DS - Product specific information
2
MA400 MA600 MA800
3
MA400 MA600 MA800
3
MA400 MA600 MA800 3
MA600 MA800
MA800
MaGnuM PRoDuct GuiDe
Current limiter
1
MB1200 MB1600 MB2000
MB1200 MB1600 MB2000
MB1200 MB1600 MB2000
MB1200 3 MB1600 MB2000
MB1200 MB1600 MB2000
MB1200 MB1600 MB2000
MB1600 MB2000
MB2000
CA013002EN—April 2017 www.eaton.com
Blown
limiter
indicator
MD2500 MD3000
MD2500 MD3000
MD2500 MD3000
MD2500 MD3000
3 MD2500 MD3000
MD2500 3 MD3000
MD2500 3 MD3000
MD2500 3 MD3000
MD3000 3
MD3000 3
23
3
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1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1