Elenos T30000, Handbook

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Hand Book T30000 -
17
Technical Office TEL: +39 532 829 965 FAX: +39 532 829 177
The electrical supply system which supplies the unit and all other equipment with power, MUST be fitted
with a CIRCUIT BREAKER with a current calibration not greater than 30% of the current drawn by
the whole transmitter. When the equipment is connected to the electrical supply, it exposes personnel
to the risk of coming into contact with high voltage lines; for this reason it is ABSOLUTELY
ESSENTIAL THAT THE CIRCUIT BREAKER IS IN THE OFF POSITION, whilst any equipment
panel remains open. Maintaining the unit's on/off switch in the off position IS NOT SUFFICIENT!
DO NOT SUPPLY ELECTRICAL POWER TO THE EQUIPMENT UNTIL ALL PANELS ARE
SHUT AND IT IS CONNECTED TO AN EARTHING POINT. An isolating transformer between the
equipment and the line supply significantly reduces the incidence of damage incurred by atmospheric
causes, greatly increases reliability and reduces the costs of faults caused by overvoltage of the line
supply. It is useful to construct a winding of about 25 turns, diameter 25-35 cm (about 1 foot) with the
line supply cables of the 3 phases and neutral before they enter the equipment. UNDER NO
CIRCUMSTANCES CONSTRUCT A WINDING WITH THE EARTH CABLE WHICH MUST BE
OF HEAVY SECTION (100mm²) AND MUST CONNECT THE EQUIPMENT TO EARTH
DIRECTLY AND WITH THE SHORTEST POSSIBLE LENGTH. The final power apparatus is
always connected to other excitation equipment which, in the majority of cases, comprises one or more
intermediate driver stages and an FM "exciter" modulator. The connections to the preceding
amplification stages and the modulator are of two types: radio frequency connections and electrical
line supply connections with a safety interlock system. The RF connections are as follows: the RF
output of the modulator is connected to the RF input of the first intermediate stage; the RF output of
the first intermediate stage is connected to the RF input of any second intermediate stage. The RF
output of the unit preceding the final T30000 amplifier is connected to the input of the low-pass filter
which finally supplies the input of the final amplifying cavity. The RF connection is complete when
the power output of the T30000 is connected to the radiating system. Connection to the radiating
system will determine the final positioning of the equipment which, for convenience, ought to be left
free until the final phase of installation. The connection of the electrical supply is more complex and
can vary according to the configuration of the transmission system components. For this reason a
series of diagrams has been supplied (see the reciprocal safety interlock connections between units)
which illustrates how the installation connections of all the equipment can be completed. Note that the
T30000 does not supply electrical power but only disconnects it via an interlock switch with a 10A
capacity. The connection scheme must satisfy two crucial constraints: if either the final power stage or
an intermediate stage fall into the protection state, the modulator must shutdown the RF output.