GE DTR GEK-106305A, Instruction Manual

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6. HARDWARE DESCRIPTION
GEK-106305A DTR Digital Tap Changer Controller 55
6. HARDWARE DESCRIPTION
WARNING
The DTR system incorporates electronic components that might be affected by electrostatic discharge
currents flowing through certain components terminals. The main source of electrostatic discharges is
human body, specially under low humidity conditions, with carpet floors or isolating shoes. If such
conditions are present special care should be taken while manipulating DDS’s modules and boards.
Operators, before even touching any component, must make sure that their bodies are not charged by either
touching a grounded surface or by using an antistatic grounded wrist bracelet.
6.1 MECHANICAL CONSTRUCTION
6.1.1 BOX CONSTRUCTION
The DTR modules are assembly in box of an standard 19’’ rack four units high, manufactured in stainless steel and
painted with gray epoxy resin. It is composed of a backbone structure, that includes the strips where all the modules
and boards are connected, plus a rear plate with all the female connectors.
All the boxes have a surge ground connection terminal, essential not only in terms of safety but also on behavior
against electromagnetic interference.
All the modules are of draw-out type, enabling easy maintenance and repair of the equipment.
The DTR also incorporates a plastic antitampering front cover. This cover keeps the relay sealed and provides a high
protection against dust and water (IP51 index according to IEC 529). The use of a push-button allows access to the
main functions without the need of removing the cover.
The front and rear views of a typical DTR equipment are shown on figures 6 and 7.
6.1.2 ELECTRICAL CONNECTIONS.
All the DTR electrical connections (voltage inputs and digital I/Os) are done through drawout terminal boards of 12
terminal blocks each located at the rear of the device.
Additionally to those terminal blocks, the DMS includes two communication ports. One front DB-9 port for local
connection and another located on the rear nameplate, used for remote connection to the PC.
This second port may be used for point-to-point connection with a central computer in the substation by means of a
multiplexer.
This second communication port may be, depending on the selected option, a RS232 with a DB-9 connector, a fiber
optics (glass or plastic) connector or finally an RS-485.
In the rear plate are also included the terminal blocks for the time synchronization through a demodulated IRIG-B
input.