AThe half-digit, or left-most '1', is always OFF (not visible) with display readings between "000" and "999" on 3½ digit meters and between "0000" and "9999" on 4½ digit meters. The half-digit is turned ON with display readings greater than or equal to "1000" on 3½ digit meters and with display readings greater than or equal to "10000" on 4½ digit meters. An enabled half-digit in combination with all other digits OFF is used to indicate an input overrange condition which occurs when the applied input exceeds the meter's measurement capability.