5
INSTALLATION
WARNING: For safety reasons the system must not be operated until the
three earthing terminals have been connected correctly.
5.1
Mechanical
The switcher is housed in a 19", 6U high rack mounted frame. All modules plug
into the frame to allow easy access for servicing and are normally protected
behind a hinged front panel. The 6U high cards each have three DIN 41612C
plugs that connect into the motherboard which carries power, signal and control
wiring between cards. Input and output connections are made by ribbon cables
connected to rear plug shells of the motherboard's DIN 41612C connectors.
Extender board type 1336 can be used to gain access to the 6U cards.
5.2
Earthing
Three system earths wired in the frame are accessible on a three-way terminal
block mounted on the rear of the power supplies. The three earths are:
Mains Earth-wired to the earth pin of the mains input connector.
Signal Earth-wired to the system 0V supply and then to the signal cable
screens.
Chassis Earth-wired to the metalwork of the frame and cable connector
metalwork.
These three earths are left entirely separate within the switching system and
can be joined on the terminal block or wired to separate earthing points as
dictated by the nature of the installation.
5.3
Modules
Confirm the correct sub-modules are fitted and pushed fully home with
reference to the label inside the front panel. Check the mains voltage is set
correctly and that the retaining screws and washers are in place. Check the
setting of links on the control card is appropriate for the system.
6521
ISS 3 DEC 97
Page 7
6521
