Disconnector Fundamentals
2
Photographs show the pressure relief capability of the PDV/PVR family of surge arresters. Notice in the “after” photo the PDV/PVR disconnector has successfully oper- ated isolating the arrester from the system. This allows the line to be put back in service and the arrester replaced at a more convenient time. O hio Brass PDV (distribution) and PVR (riser pole) arresters are normally furnished with a disconn ector (also called an isolator). The disconn ector is incorporated within the housing of the insulating base bracket at the bottom stud area. All Ohio Brass arresters furnished with the finned insulating base PDV/PVR DISCONNECTOR FUNDAMENTALS TIME-CURRENT CHARACTERIS TICS OF DISCONNECTORS PDV / PVR ■ bracket include the ground lead disconnector. The disconnector performs a vital service when a rare arrester failure occurs. Subsequent to arrester failure, the disconnector reacts to a rapid increase in 60 cycle current flow through the arrester. Voltage develops across a resistor in the disconnector assembly allowing it to sparkover a small gap. This causes the arc to terminate on a cartridge. As the cartridge detonates, it separates the ground lead from the failed arrester. As the circuit is broken, system lockout is prevented. If a shorted arrester would remain connected to the line, then it would not be possible to re-energize the line. The disconnector also serves as a time saving visual aid in identifying the failed arrester from replacment. Arresters in service are continuously energized with 60 Hz voltage. The disconnector must not operate under normal service conditions. Standards require the arrester to be tested with the disconnector installed thus requiring the discharge operation characteristics to be verified. Examples of tests performed with the disconnector installed are duty cycle, high current, low current-long duration and contamination. The time for operation of the disconnector is verified by subjecting the sample to be tested to rms currents ranging from 20 through 800 Amps. The time for the disconnector to operate is plotted as a function of current magnitude. The time current curve for our PDV/ PVR arrester is shown when tested per ANSI/IEEE C62.11-1993 tests. ♦ A RRESTERS ♦ © Copyri ght 2004 Hubbell • 210 North All en Stre et • Centralia, MO 65240 NOTE: Because Hubbell has a policy of continuous product improvement, we reserve the right to change design and specifications without notice. ® POWER SYSTEMS, INC. EU1487WB TiPS NEWS View from Vol. 3 No. 1 JAN 1997 & 573-682-5521 Fax 573-682-8714 http://www.hubbellpowersystems.com
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Transcript of Disconnector Fundamentals
7/28/2019 Disconnector Fundamentals
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Photographs show the
pressure relief capabilityof the PDV/PVR family of
surge arresters. Notice in
the “after” photo the
PDV/PVR disconnector
has successfully oper-
ated isolating the
arrester from the system.
This allows the line to be
put back in service and
the arrester replaced at a
more convenient time.
Ohio Brass PDV (distribution) and PVR (riser pole) arresters are normally furnished with a disconnector (also called an isolator). The disconnector isincorporated within the housing of the insulating base bracket at the bottomstud area. All Ohio Brass arresters furnished with the finned insulating base
PDV/PVR DISCONNECTOR
FUNDAMENTALS
TIME-CURRENT CHARACTERISTICS OF DISCONNECTORS PDV / PVR
■
bracket include the ground lead disconnector.
The disconnector performs a vital service when a rare arrester failure occurs. Subsequent toarrester failure, the disconnector reacts to a rapid increase in 60 cycle current flow throughthe arrester. Voltage develops across a resistor in the disconnector assembly allowing it tosparkover a small gap. This causes the arc to terminate on a cartridge. As the cartridgedetonates, it separates the ground lead from the failed arrester. As the circuit is broken,
system lockout is prevented. If a shorted arrester would remain connected to the line, then it would not be possible to re-energize the line.
The disconnector also serves as a time saving visual aid in identifying the failed arrester fromreplacment.
Arresters in service are continuously energized with 60 Hz voltage. The disconnector mustnot operate under normal service conditions. Standards require the arrester to be tested withthe disconnector installed thus requiring the discharge operation characteristics to beverified. Examples of tests performed with the disconnector installed are duty cycle, highcurrent, low current-long duration and contamination.
The time for operation of the disconnector is verified by subjecting the sample to be testedto rms currents ranging from 20 through 800 Amps. The time for the disconnector tooperate is plotted as a function of current magnitude. The time current curve for our PDV/PVR arrester is shown when tested per ANSI/IEEE C62.11-1993 tests.
♦ A RRESTERS ♦
© Copyright 2004 Hubbell • 210 North Allen Street • Centralia, MO 65240
NOTE: Because Hubbell has a
policy of continuous product
improvement, we reserve the
right to change design and
specifications without notice.
®
POWER
SYSTEMS, INC.
EU1487WB
TiPS NEWSView from Vol. 3No. 1 JAN 1997
&
573-682-5521 Fax 573-682-8714 http://www.hubbellpowersystems.com
