User manual

20 MLC-810 TUFF VIEW LCD Monitor
5.2.1. Reverse polarity protection
The monitor has reverse polarity protection on the power input, so external protection is
not required.
5.2.2. Transient protection
The monitor has a sophisticated input transient protection circuit. It has been designed for
in-vehicle applications, to protect against damage from load-dump in 12V and 24V
vehicles. In non-vehicle applications this circuit provides a high level of transient
protection against voltage surges, etc.
5.2.3. Input fuse considerations
The monitor has an internal safety fuse fitted. The current rating of this fuse is much
higher than required for normal operation. It is there as a final precaution, and is not
intended to replace an in-line fuse that would normally be fitted.
Some points to consider when selecting an external fuse include:
 Slow blow vs fast blow.
 Maximum input current – at the input voltage range. The higher the input voltage,
the lower the input current.
 Input current during engine crank.
 Fuse current rating vs ambient temperature – if the monitor is going to be used at
the extremes of the its temperature range.
5.3. Environmental Factors
5.3.1. Temperature
The monitor should not be exposed to ambient temperatures above 65C, while operating
at maximum brightness. Doing so might overheat the liquid crystal and clear the LCD
panel – this will permanently damage the liquid crystal cells in the LCD panel, and prevent
them from being able to turn on and off.
5.3.2. Humidity
The monitor should not be opened up in areas with very high humidity. High-humidity can
cause moisture to enter and accumulate in the unit. This moisture can cause corrosion of
internal components and degrade properties such as electrical resistance and thermal
conductivity. Extreme moisture build-up inside the unit can result in electrical shorts,
which can cause serious damage to the system.
5.3.3. Altitude
Operating the unit at high altitudes (low pressures) reduces the efficiency of the heatsink.
It can also cause sealed components with internal pressure, such as electrolytic
capacitors, to fail or perform at reduced efficiency.
The unit is not designed to operate at very high altitudes in un-pressurised compartments.