User`s manual

DIGITAL-LOGIC AG MPC40/A/B/C, MPC41 Manual V1.4C
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3.5 Safety: Protection of the Output Currents
The computer system limits the current of all peripheral supply outputs with fuses or with electronic cur-
rentlimiters. The following table shows the maximum available currents at each peripheral connector:
Nominal max. current: Max.Current
USB: 0.5 Amp. @ 5V 1 Amp. with resistor limiter
KB/MS: 0.1 Amp. @ 5V 0.2 Amp. with polyfuse
VGA: 0.1 Amp. @ 5V 0.2 Amp. with polyfuse
Firewire 0.5 Amp. @ 12V 2 Amp. with electronic limiter
3.6 Safety: Load Dump Protection in 12V/24V systems
Currently there are two types of TVS devices integrated in the
computersystem for the 12/24V automotive systems to protect against
load dump: silicon-based single-junction Zener diodes and zinc-oxide-
based metal oxide varistors (MOV). Even though Zener diodes and
MOVs operate on different physical mechanisms, they both offer a
typical 28V clamp voltage for the 12/24V systems.
Input Varistor: B72220S300K (Infineon) Vbreak=30V
3.7 Safety: Ground Potential
t.b.d
3.8 Safety: Power On/Off Switch
The power on/off switch does not cut all power of the complete equipmement. In the OFF-state is a micro-
contoller still working, to supervise the wakeup events (switch, remote-on, wake-on-LAN, wake-on-events)
[MIL STD 454M]
The system is consuming a power of approx. 10mW in the poweroff state.
The power switch is clearly identified and located on the front panel [MIL-STD-545M]
The power switch is protected from accidental contact, which causes a power on/off. The power switch must
be activated over a defined periode 1-3sec.
When the system is opened, the replicator unit must be removed and in this way no external power supply is
available. Take care, that the internally installed batteries are even connected to the system.
3.9 Safety: Batteries Inside the Device
The system has one integrated backup lithium batteries (RTC). The batteries compartments are
not vented. The system enclosure prevents the operator from an exploding battery cell.