MarelliMotori MARK VX Manual Del Usuario página 17

8. TROUBLESHOOTING AND OPERATIONS
8.1. INTRODUCTION
The following procedure integrates the Troubleshooting section of the Use and Maintenance Manual for the Marelli
generator, paying particular attention to the regulation system aspects: the main problems you can encounter
during normal operation of the regulator are particularly covered, relating only to the regulation.
It is however possible that some of the problems listed can also be attributed to other parts of the generator and not
just the regulator; it is also possible that certain faults on the regulator are caused by problems or defects outside
the machine, for example, by devices not manufactured by Marelli Motori connected to the machine or due to
improper use by the operator, etc.
For this reason, you are always advised to consult all the documentation available to you, in particular the regulator
User Manual, the Use and Maintenance Manual of the generator and the connection diagrams normally supplied,
as well as the documentation for all the devices not manufactured by Marelli Motori relevant to regulation.
The following section provides general information on the type of controls to carry out in case
of malfunctioning or problems with regulation. It integrates but does not substitute in any way
the other instructions/procedures relevant to control, calibration and protection which are
indicated in the regulator User Manual and which must be read carefully.
By following the steps below, always consider the Safety Precautions and the detailed
instructions for each operation performed, supplied in the documentation accompanying the
generator.
Any changes and/or intervention on regulator connections or on the electrical parts connected
to it must ALWAYS be carried out with the generator stopped and the regulator board not
powered.
Any other type of physical intervention on the regulator and/or the generator must be carried
out with the machine stopped, unless specifically indicated.
When the documentation available does not suffice to solve the problem, contact Marelli Motori
Service for further instructions.
8.2. TROUBLESHOOTING
In case you experience any of the difficulties listed in this chapter please follow the troubleshooting and repair
procedure described below.
NOTE: In the event were physical damage were found on the board and/or its components, do not restart the
generator and remove the damaged board. Then call Marelli Motori Service for further instructions.
With generator to rated speed, without load, the voltage at the output terminals is equal to the residual
voltage of the machine or lower than the nominal one.
Step 1. Check the connections.
In case of missing or incorrect connections, reconnect following the diagram supplied with the
generator.
Otherwise, go to Step 2.
Step 2. Check that the inner fuse is not broken.
If it actually is, replace it with a new fuse having the same features.
Otherwise, go to Step 3.
NOTE: If while restarting the generator the new fuse immediately breaks, go directly to Step 5.
Step 3. Check the calibration of the VOLT meter.
In particular, with VOLT fully rotated counter-clockwise, the reference voltage is at a minimum level
and the controller does not provide excitation energy.
Reset the VOLT meter.
Otherwise, go to Step 4.
Step 4. Measure the residual voltage value on supply terminals U and 0 of the controller, that is check if the
residual magnetism of the machine is sufficient to arise self-excitation energy (both in case of
supply from the main terminals and from auxiliary winding).