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8.4 Display backlight
The BA558C can be supplied with LED
backlighting to improve display contrast when the
instrument is installed in a poorly illuminated area.
The backlight is electrically segregated from the
measuring circuit and may be powered from any
18 to 30V dc supply.
Fig 14 Display backlight
Reducing the supply voltage below 18V, or fitting a
current limiting resistor in series with the supply will
reduce the display brilliance
8.5 Additional front panel protection
Although the BA558C has an IP65 sealed front
panel, for installations in hostile environments
where the instrument is likely to be damaged by
impact an additional front cover is available.
The BA398 is a robust transparent cover which is
secured to the panel by six screws and sealed with
a neoprene gasket. It completely covers the front
of the rate totaliser and therefore prevents the
BA558C front panel push-buttons being operated.
