SPECIAL INSTRUCTIONS FOR ELECTRONIC SUBSYSTEMS 5-21 E UROCARGO Euro 4/5 In addition, definitely respect the following precautions for the protection of the vehicle’s electronic components: Never disconnect the connectors of the control units with the engine running and control units powered. Do not power the components interlocked with electronic modules with the vehicle’s nominal voltage via movable cables. The control units provided with a metal casing must be connected to the ground of the system with screws or bolts, unless specified otherwise. When required by the application of additional equipment, it is necessary to install diodes to protect against any inductive surges in current.
The ground signal from the analogue sensors must be wired solely on the specific receiver; further ground connections could distort the output signal from these sensors. The bundle of cables for electronic components with low signal strength must be arranged in parallel to the metal surface of refer- ence, that is sticking to the chassis frame/cab structure, in order to reduce the parasite capacities to a minimum; separate the route of the bundle of cables added to the existing one as far as possible.
The added systems must be connected to the ground of the system with the greatest care (see point 2.1.1); the related wirings must not be set alongside the existing electronic circuits on the vehicle, so as to avoid electromagnetic interference. Make sure that the wirings of the electronic devices (length, type of conductor, location, clamps, connection of the shielding, etc.) are in compliance with the original IVECO setup. Carefully restore the original system after doing any work.
5.8.2 Electromagnetic Compatibility It is recommended to use electric, electromechanical and electronic appliances that meet the prescriptions of electromagnetic emission and immunity at both the radiated and carried level, described below: The required level of electromagnetic immunity of the installed electronic devices on the vehicle at 1 metre from the transmitting antenna must be:
- immunity of 50V/m for devices that perform secondary functions (they do not impact the direct control of the vehicle), for vari- able frequencies from 20 MHz to 2 GHz - immunity of 100V/m for devices that perform primary functions (they do not impact the direct control of the vehicle), for variable -frequencies from 20 MHz to 2 GHz. The maximum permissible amplitude of the transitory voltage for equipment powered at 24V is +80V measured at the terminals of the artificial network (L.I.S.N.) if bench tested, otherwise if tested on the vehicle it must be measured at the most accessible point near to the interfering device.
NOTE The devices supplied at 24V must be immune to negative interference such as spikes of -600V, positive spikes of +100V, bursts of ± 200V. They must work correctly during the phases of lowering the voltage to 8V for 40mS and to 0V for 2 ms. In addition they must withstand the phenomenon of load dumping to values of 58V. The maximum levels measured at the bench of the radiated and carried emissions produced both by the devices and at 24V are given in the following Table 5.24. Electrical system: modifications and drawing-off power Print 603.93.431 Base - January 2008