MarelliGenerators M40FA640A/A MARK I, Руководство пользователя

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8
ENGLISH
SIN.NT.015.6 – M40FA640A/A Issued 04.2010
USE OF POTENTIOMETERS
VOLT - potentiometer to change the output voltage of
the generator:
Normally the internal potentiometer VOLT allows possibility
of adjusting the voltage in a wide range (i.e. between 200
and 560 V); to obtain a finer possibility of voltage setting or
to adjust the voltage from the control panel, or in order to
limit the voltage range, an external potentiometer can be
connected to the terminal “P” and “Q” (resistance about
100kOhm, 500mW, to /- 5% voltage regulation).
⇒
increases voltage
FREQ - potentiometer to change the low speed
protection:
usually it is set at the factory in order to reduce the
excitation when speed becomes lower than 90% of rated
speed at 50 Hz. By removing the bridge which normally
shorts the terminals “Hz” and “60”, the speed protection
acts properly for 60 Hz operation.
By acting on potentiometer FREQ it is possible to adjust
further (in case should it be necessary) the frequency at
which the low-speed protection is effective.
⇒
decreases frequency of intervention
AMP - potentiometer to change the over-excitation
limiter:
it permits to set the excitation voltage threshold of the over-
excitation limiter.
The default setting of this potentiometer is at the maximum
excitation voltage threshold.
⇒
increases the over excitation threshold.
STAB - potentiometer to change stability:
by rotating it clockwise stability increases, but response
time becomes larger.
⇒
increases response time, increases stability
SLOPE - potentiometer to change the low speed
protection characteristic slope:
with the micro-switch 4 OFF, this potentiometer allows to
increase or decrease the under speed ramp slope, and set
the voltage droop for a fixed reduced speed.
⇒
decreases the voltage droop for a fixed frequency
intervention.
PAR - potentiometer to change the droop
This potentiometer allows to change the voltage droop in
load conditions.
⇒
the droop increases