Abstract: A digital panel meter adapted for replacement of a standard analog panel meter and designed to selectively receive different ranges of input signals such as AC or DC input signals. The meter circuitry employs an analog-to-digital converter having multiple digits, an input circuit including a range circuit, an operational amplifier and filter circuitry. A relay is tripped for signaling the attaining of a trip point. An audible alarm is provided that may be enabled or disabled and that may be operated in either continuous or short term modes.

Abstract: A digital panel meter that is mounted in a panel and that is comprised of a housing for containing a circuit assembly having a digital display at the front of the housing. A bezel is adapted to cover the front of the housing and has a transparent window for the viewing of the digital display. The bezel includes a pair of elongated bezel locking arms that are spacedly disposed and extend towards the rear of the housing where they interlock with the housing. The housing is also provided with locking tabs for securing the housing to the panel.

Abstract: The meter is primarily adapted to replace a standard analog panel meter and is designed to selectively receive different ranges of input signals such as DC input signals in ranges extending from 50 mVDC to 500 VDC. In the disclosed embodiment there are four ranges also adapted to receive AC input signals in ranges extending from 100 mVAC to 480 VAC. Preferably, a jumper is used to select the different ranges. The jumper is readily accessible at the rear of the meter. The meter circuitry comprises an analog to digital converter having three digit, seven segment display and input circuitry including a range circuit, an operational amplifier and filter circuitry coupling serially to the converter.