69
Instruction Booklet
IB 33-790-1J
Effective November 2010
Instructions for Low Voltage Power
Circuit Breakers Types DS and DSL
EaToN CorPoraTIoN www.eaton.com
Section 9 - DSL Circuit Breakers and Fuse Trucks
9.0 GENERAL
DSL circuit breakers are coordinated combinations of
standard DS circuit breakers and integrally mounted
series connected current limiters. They are available in
two frame sizes, DSL-206 and DSL-416. The primary
purpose of the current limiters is to extend the interrupt-
ing rating of the DS circuit breaker up to 200,000
amperes RMS symmetrical current. If the current limiters
are sized per Table 5, the circuit breaker will function and
interrupt the routine fault currents. Infrequent high faults
will be cleared by the limiter. The limiters protect the cir-
cuit breaker on faults above the rating of the breaker. The
limiters will blow below the circuit breaker short-time rat-
ing if the fault currents equal the system maximum
capacity.
In some applications the current limiters will be sized
smaller than necessary for protection of the DSL circuit
breaker in order to provide protection for downstream
equipment. When this is done, the current limiters will
blow on fault currents which could have been satisfacto-
rily interrupted by the basic circuit breaker.
Type DS-3200 and DS-4000 fuse trucks provide for sepa-
rate mounting of Class L current limiting fuses on drawout
trucks for use in series with DS-632 and DS-840 circuit
breakers respectively. This separate mounting is made
necessary by the size of the Class L fuses and their high
temperature characteristics.
9.1 DSL CURRENT LIMITERS
Available current limiter ratings and their recommended
applications are listed in Table 5. Do not replace limiters
with sizes other than permitted by the table. Eaton
DSL current limiters have been tested and approved
by Underwriters Laboratories, Inc. for use in DSL circuit
breakers when applied according to Table 5. They are not
electrically or physically interchangeable with current lim-
iting fuses of any other design.
The current limiters are held in place in an extension pro-
vided on the back of the circuit breaker. This extension
makes the DSL circuit breakers eight inches deeper than
the corresponding DS circuit breakers (see Figures 77,
78, and 79). The current limiters can only be removed from
the circuit breaker and replaced when the circuit breaker
is removed from its associated compartment. For this
reason, there is no fixed mounted version of the DSL cir-
cuit breakers.
ø Minimum nuisance blowing of limiters
* Use only when current limiting is required for downstream equipment. If long
delay pick-up is set above 100%, minimum limiter ratings should not be used.
** Highest rating that will protect breaker.
Fig. 77 DSL-206 Breaker Side View.
9.2 BLOWN LIMITER INDICATOR
The Blown Limiter Indicator provides a visual indication
on the front of DSL circuit breakers when a current limiter
in any phase has interrupted a short circuit. It also
insures that the circuit breaker will be tripped when any
current limiter has blown, to prevent single phase power
being applied to a three-phase load (see Figure 80).
This device consists of three solenoids, each connected
in parallel with one of the limiters. When a limiter is
blown, the resulting voltage across the open limiter
causes the associated solenoid to operate, tripping the
circuit breaker mechanically and extending an indicator
through the front cover of the circuit breaker (see Figure
78). The indicator will remain extended and the breaker
will be held trip-free until the reset button is pushed. If the
device is reset and the breaker reclosed on an energized
Table 5 - Sensor and Limiter Ratings
Breaker
Type
Sensor
Rating
ø Recommended
Limiter Ratings
*Minimum
**Maximum
DSL-206
DSL-206
800A
600A
1600A
1200A
1200A
800A
2000A
2000A
DSL-206
Less than
600A
1200A
125% or more of
sensor rating
2000A
DSL-416
1600A
3000A
3000A
3000A
DSL-416
1200A
2500A
2000A
3000A
DSL-416
Less than
1200A
2000A
125% or more of
sensor rating
3000A
