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NOVA™ STS Single-Tank, Triple-Single, Electronically Controlled Recloser
INSTALLATION AND OPERATION INSTRUCTIONS
MN280046EN May 2016
Test results for NOVA STS reclosers equipped with the
internal voltage sensing option will be influenced by the
source-to-ground connected sensing resistor.
The following tests should be applied to the NOVA STS
Single-Tank, Triple-Single recloser system:
Test 1
1. Close the recloser contacts.
2. Ground the recloser.
3. Connect terminals 2, 4, and 6 (see Figure 16) together.
4. Apply proper test voltage (see Table 15) to terminals 2,
4, and 6.
5. The recloser should withstand the test voltage for 60
seconds.
Test 2
1. Close the recloser contacts.
2. Ground the recloser.
3. Ground terminal 2 and terminal 6.
4. Apply proper test voltage to terminal 3.
5. The recloser should withstand the test voltage for 60
seconds.
Test 3
1. Open the recloser contacts.
2. Ground the recloser.
3. Connect and ground terminals 1, 3, and 5 (see Figure
16).
4. Connect terminals 2, 4, and 6.
5. Apply proper test voltage to terminals 2, 4, and 6.
6. The recloser should withstand the test voltage for 60
seconds.
7. Reverse the connections: ground terminals 2, 4, and 6.
8. Apply test voltage to terminals 1, 3, and 5 for 60
seconds.
9. The recloser should withstand the test voltage for 60
seconds.
Withstand test results
The high-potential withstand tests provide information on
the dielectric condition of the recloser and the vacuum
integrity of the interrupters.
If the recloser passes the closed-contacts tests (Tests 1
and 2), but fails the open-contacts test (Test 3), the cause is
likely to be in the interrupter assembly. Retest each phase
individually to determine the failed phase or phases.
If a recloser fails the closed-contacts test, the cause is likely
to be a diminished electrical clearance or failed insulation.
If the recloser does not pass Tests 1, 2, or 3, contact an
authorized service center or your Eaton’s Cooper Power
series product representative.
otee:
N
Test results for NOVA reclosers equipped with the
internal voltage sensing option will be influenced by
the source-to-ground connected sensing resistor,
especially if DC high-potential testing is performed.
Module flashover service
If a NOVA recloser module was exposed to an external
flashover, an inspection process is recommended to assure
proper operation of the recloser. Should the NOVA recloser
exhibit external flashover attributes (carbon tracking or
discoloration), the following procedure is recommended:
1. Bypass and remove the recloser from service as
described in this manual.
2. Confirm the dielectric strength of the recloser by
performing high-potential withstand test. Refer to the
High-potential withstand testing
section of this
manual.
3. Inspect the housing and lifting lugs for damage that
may affect electrical and/or mechanical performance.
If there is damage to either the housing or lifting lugs
they must be replaced or repaired.
4. Inspect module for damage to the terminals. Remove
any damaged terminals and replace.
5. Inspect module for damage to the module conductor
rods (0.63” diameter threaded rods on top and side of
module for affixing terminals). If there is damage to the
module rods, the module must be replaced. Contact an
authorized service center or your Eaton’s Cooper Power
series representative.
6. Inspect the operating rod for damage. Check the
module surface and major and minor sheds for cracks,
holes, and major chips. If damage is present, the
module must be replaced. Contact your Eaton’s Cooper
Power series product representative.
7. If no damage is found, clean the module with isopropyl
alcohol and a scratch-free, nylon scouring pad to
remove any carbon deposit.
8. Before returning to service confirm electrical operation
by opening and closing the recloser with a control.
Confirm the dielectric strength of the recloser by
performing a high-potential withstand test. Refer to
the
High-potential withstand testing
section of this
manual.
