MarelliGenerators M40FA640A/A MARK I, Руководство пользователя

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ENGLISH
SIN.NT.015.6 – M40FA640A/A Issued 04.2010
CONTROL TERMINALS
“Hz”, “60” : terminals for changing the low speed protection
terminals
“P”, “Q” : terminals for connection of external trimmer
(100kOhm).
“6”, “8”: input terminals for connections of external control
systems (input for D.C. voltage , +/-3 Vdc). The terminal
“ ” is to be used only in case of special connections.
TERMINALS for interconnecting with over-boosting
excitation systems
“+”, “-” : output terminals (positive, DC, and negative, DC)
“9” : voltage sensing
EXTERNAL POTENTIOMETER
At the terminals “P” and “Q” an external trimmer (minimum
rating 500mW, resistance about 100kOhm) can be
connected. By acting on such trimmer, it is possible to
obtain a voltage regulation of about +/- 5 % around the
nominal voltage. By using a 200kOhm potentiometer it is
possible to obtain a voltage regulation of about +/- 10 %.
The trimmer is connected anyway (through the regulator) to
the output of the generator and then it represents a live
part.
UNDERFREQUENCY LIMITER
The regulator is provided with internal circuits in order to
reduce the excitation, when running at low speed, in order
to avoid damages to the excitation system of the generator
(i.e. to the regulator, to the exciter field, to the rotating
rectifier, main rotor).
The potentiometer “FREQ” fixes the corner-frequency, that
is the frequency at which the limiter operates. Below that
particular frequency, red LED switches-on and the voltage
of the generator reduces further with speed reduction.
By setting the micro-switch nr. 4 in OFF position, the
voltage reduction is smaller and is close to be proportional
to the speed reduction (voltage reduction is settable by the
potentiometer ”SLOPE”).
ANALOGUE INPUT
The AVR accepts a voltage analogue input of +/-3Vdc
maximum, to control the exciter field of the generator.
This input has to be applied to terminals 6 and 8.
In case of single operation, a maximum change of +/-3Vdc
of the analogue input leads to a maximum change of +/-
25% of the generator voltage, with respect to the rated
generator voltage.
A value of 0Vdc does not lead to any change in excitation.