12. BACKLIGHT
To improve display contrast the BA578C can be
supplied with LED backlighting to improve display
contrast when the transmitter is installed in a poorly
illuminated area. The backlight is segregated from
the measuring circuit and may be powered from
any 18 to 30V dc supply.
Fig 13 Backlight power supply
The brilliance of the display backlight may be
reduced by decreasing the supply voltage below
18V, or by adding a current limiting resistor in
series with the supply
.
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