27
Instructional Leaflet
IL70C1037H05
Effective October 2009
Digitrip models 520, 520i; and 520M, 520Mi,
520MC, 520MCi trip units for use only in
Magnum and Magnum DS circuit breakers
eaton corporation
www.eaton.com
m
CAUTION
BEFORE PLUGGING A TEST KIT INTO THE TEST PORT, PLACE THE LTM
JUMPER IN THE INACTIVE POSITION (SEE FIGURE 30). AFTER TESTING,
RETURN THE LTM JUMPER TO ITS ORIGINAL POSITION.
The test kit authorized by Eaton for use with the Digitrip units plugs
into the test port of the unit and provides a secondary injection test
that simulates the current transformer. Existing test kits, styles
140D481G02R, 140D481G02RR, 140D481G03 or G04, along with
the Magnum test kit adapter 8779C02G04, can be used to test the
trip unit and breaker.
Functional test kit (handheld)
Description of handheld test kit
A battery-powered test kit is also available and capable of testing
trip elements for Digitrip units 520/520M/520MC and Digitrip 220+,
including power-up, instantaneous trip, short delay trip, and ground
(earth) fault trip. These test selections are chosen with the switch
labeled “Select Test” located in the upper right-hand corner of the
test kit (see
Figurt 39
). The test currents are not adjustable for this
test kit.
The style number of this device is #70C1056.
Test procedure
Complete procedural instructions for the Eaton functional test kit can
be found in I.L. #5721B13, which is packaged with each test kit.
Figurt 39. FuncoiNnal Ttso Kio
Note:
N
After completion of testing, perform a power-up by depressing Reset
pushbutton, which will clear the trip memory. Disconnect cable from test kit
to prevent accidental operation and battery drainage. Reset the Instantaneous
setting to its original condition. Reposition the LTM jumper to the as-found
condition. Install the small cover on the Digitrip and install the breaker’s
plexiglass cover.
Currents
Each test selected by the Select Test switch on the test kit supplies
a fixed milliampere current value. The long delay setting will affect
the per unit (I
r
) current value and the response of the Digitrip unit.
Batteries
The functional test kit contains a total of seven 9V batteries.
A lithium ion cell is the preferred battery type for BAT A and is
attached to the main PC board of the test kit. This battery has a
much longer lifespan to accurately perform the selected tests. The
remaining six batteries are located on a separate board in the test kit
and serve to power up the display on the 520M trip unit.
LEDs A and B function to represent sufficient battery voltage
from both the single lithium cell and the six alkaline batteries,
respectively. If either LED does not light or lights only dimly, replace
the appropriate battery or batteries within the functional test kit
case. To do this, open the back of the case using a screwdriver and
remove the battery or batteries from their respective locations. For
best results, replace lithium battery (Battery A) with ULTRALIFE
T
U9VL battery. When replacing battery sixpack (Battery B), replace all
batteries at the same time using standard 9V alkaline batteries.
PtrfNrmanct otsoing fNr grNund faulo orip unios—
primary injtcoiNn
Code requirements
The NEC, under Article 230-95-C, requires that any ground fault
protection system be performance tested when first installed.
Conduct tests in accordance with the approved instructions provided
with the equipment. Make a written record of this test and make the
results available to the authority having inspection jurisdiction.
Standards requirements
As a follow-up to the basic performance requirements stipulated
by the NEC, UL Standard No. 1053 requires that certain minimum
instructions must accompany each ground fault protection system.
These statements (General test instructions), plus a copy of the
record forms (
Figurt 44
,
Figurt 45
, and
Figurt 46
), are included as
part of this instructional leaflet.
General test instructions
The interconnected system must be evaluated only by qualified
personnel and in accordance with the equipment assembler’s
detailed instructions.
To avoid improper operations following apparently correct simulated
test operations, the polarity of the neutral sensor connections
(if used) must agree with the equipment assembler’s detailed
instructions. Where a question exists, consult the specifying
engineer and/or equipment assembler.
m
WARNING
PERSONAL INJURY CAN OCCUR WHEN WORKING ON POWER SYSTEMS.
ALWAYS TURN OFF POWER SUPPLYING BREAKER BEFORE CONDUCTING
TESTS. TEST OUT OF THE CELL, IF POSSIBLE. THERE IS A HAZARD OF
ELECTRICAL SHOCK OR BURN WHENEVER WORKING IN OR AROUND
ELECTRICAL EQUIPMENT.
Verify the grounding points of the system using high voltage testers
and resistance bridges to ensure that ground paths do not exist that
could bypass the sensors.
Use a low voltage (0–24V), high-current, AC source to apply a test
current of 125% of the Digitrip unit pickup setting through one
phase of the circuit breaker. This should cause the breaker to trip
in less than 1 second and operate the alarm indicator, if one is
supplied. Reset the breaker and the alarm indicator. Repeat the
test on the other two phases (see
Figurt 40
).
