MarelliMotori M40FA610A MGC I Manuel Utilisateur page 14

9. CONTROL BY MEANS OF EXTERNAL DEVICE
9.1. External potentiometer
An external potentiometer for fine setting of the voltage reference can be connected to the terminals P and Q. This allows to:
- change the voltage set-point by means of remote control device;
- set the generator voltage reference with accuracy higher than the one of the internal regulator potentiometer VOLT.
External potentiometer specifications are the following:
Setting range Potentiometer specifications
±5% 1 kΩ - 2 W minimum
±10% 2 kΩ - 2 W minimum
9.2. DC voltage signal from external control device
The AVR accepts a DC voltage analogue input of +/-3 V (maximum range), 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 +/-3 V 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 0 V at 6 and 8 terminals does not lead to any change in excitation.
The analogue input is usually used for the voltage regulator control by means of the Marelli power factor regulator, for parallel
operation with the grid.
This input can be also connected to external devices not made by Marelli, for remote control of the generator voltage or the
excitation during parallel operations (voltage matching and power factor regulation), as long as those devices were equipped
with suitable outputs (insulated outputs, and voltage regulation range not higher than +/-3 V).
WARNING: in the case of parallel with the grid, and voltage regulator controlled by an external device by means of the
analogue input, pay attention to the analogue input voltage value after the load rejection.
In this particular case, in order to avoid any dangerous generator over-voltages, the voltage value between the terminals 6 and
8 must be reduced to 0 V or to any values leading to a generator voltage not exceeding the rated + 5%.
10. FUSE
The voltage regulator is provided with an internal protecting fuse (which acts in case of faults on the regulator or very large
overloads on exciter circuit).
11. EMI SUPPRESSOR
The AVR is provided with an internal Electromagnetic Interference filter: this interference suppression system permits to obtain
compliance with relevant EMC standards on MARELLI MOTORI generators.
12. ACCESSORY
Description
Fuse (Ultra rapid, ceramic, 10 A – 500 V)
External potentiometer (1 k - 2 W)
13. MAINTENANCE
The only preventative maintenance required for the regulator is to check the connections between the regulator itself and the
system: make sure they are clean and tight and that the cabling shows no imperfections or damage.
The M40FA610A/A is a circuit board protected by a polyurethane resin that protects the device from dampness, dust and
aggressive environments: in case of malfunction or damage of any type, any modifications, repairs or adaptations not previously
approved by Marelli Motori are forbidden.
Part number
963823010 - 10003249
963824410 - 10010339
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