MarelliMotori MARK V Manual Del Usuario página 25

6.2. SPECIAL CONNECTIONS: EXTERNAL DC VOLTAGE SIGNAL
In particular cases, it is possible to connect to P and Q an external device capable to provide a DC
voltage signal to the regulator for generator excitation control.
This signal must be within the range 0 to +10 V (with P positive terminal and Q negative terminal).
WARNING:
the external device output connected to P and Q must be galvanically insulated.
The setting procedure is the following:
Generator in single operation, no load, must be run.
-
Set VOLT potentiometer in order to have approximately 50% of the rated generator voltage.
-
Connect the external device as per following figure:
-
and provide a voltage V
Set again VOLT in order to have approximately the rated generator voltage.
-
It is now possible to control the generator excitation by means of the voltage provided to P and Q;
that control is approximately linear within the following range:
WARNING: Always provide the voltage V
of a negative voltage to P and Q is forbidden, in order to avoid dangerous over-
excitation. Should you have any doubts about the connection and/or use of P and Q
terminals, please contact Marelli Motori Services.
963857121_M
+10 Vdc
Vext
+
-
0 Vdc
= +5 V to P and Q terminals.
ext
V
ext
+3 V
-3 V
EN
Mark V M16FA655A
P
Q
V
gen
-20%
+20%
BEFORE every generator start. Application
ext
Marelli Motori
25