Murphy by Enovation Controls ATH-30 12/24 VDC Analog Tachometer/Hourmeter (20700249)

The ATH-30 tachometer/hourmeter is a rugged instrument with solid-state circuitry for indication of engine RPM and elapsed engine running time. It is equipped with a ring nut for mounting into a standard 3-3/8 in. (86 mm) dash mounting hole. A full 240° sweep of the pointer gives an accurate indication on a large easy-to-read scale, and the dial can be illuminated for night reading. This ATH Series' tachometer indicates engine speed in revolutions per minute (RPM), while the hourmeter records elapsed engine running time when the engine speed is greater than 100 RPM. Calibration has also been improved and is now accomplished with a single push button on the back. Features: * Improved quality * New, easy one-button calibration procedure * 12 & 24 VDC versions are included in one model number * Every model will accept all signal sources: alternator, magnetic pickup or ignition * LED backlight, no bulbs to change * Easy ring clamp for installation. The tachometer is for negative ground or isolated electrical systems. If the instrument is connected to reverse polarity, it will not operate until proper connections are made. It is powered by a 12 or 24-volt battery (operating range: 10-32 VDC). Not intended for use with Capacitive Discharge (CD) ignitions or magnetos, only for inductive, automotive-type ignitions. The tachometers are powered by a 12 or 24-volt battery and are reverse polarity protected. These units are for negative ground, positive ground or isolated electrical systems. They are specially designed for use on truck, marine, industrial or stationary engines. Replaces: ATHS-30-12 (20700180), ATHS-30-24 (20700210), ATHS-40 (20700142), ATHA-30-12 (20700184), ATHA-30-24 (20700206), and ATHA-40 (20700137).

• A Rugged Instrument with Solid-State Circuitry for Indication of Engine RPM and Elapsed Engine Running Time