What is an hour meter?

Answer 1

There are different kinds. The kind you find on an aircraft or other equipment measures the time in operation, usually for purposes of performing maintenance at specified times, or possibly for charging a per-hour fee. It is often referred to as a Hobbs meter, after one manufacturer. It typically consists of a motor that turns numbered wheels having the same appearance as an auto odometer. Some can be reset with a pushbutton, but most can't, because it would defeat the purpose if someone could reset the hours at will. There is one version consisting of a glass tube filled with red fluid (resembling a small thermometer) in which, through electro-chemical action, the fluid advances across the length of the tube as time under power passes. The latter is a more coarse display than the motor type and is used for general information only. Both kinds advance when power is applied, but may be additionally keyed by supplemental information, such as an oil pressure switch of an engine that would give true time in operation. Sometimes only the power only is used on the theory that the time an ignition switch is on but the engine is not actually running is likely to be small and unimportant. The motor type may be replaced by a solid-state version resembling a digital clock, but the use is identical. The electric meter on one's house is a watt-hour meter. It displays the power times the time, which is energy and what you pay for. There are fully electronic meters, but most buildings have the type wherein an aluminum disk is spun by the energy and turns clock-like hands for the meter reader to see. The disk has two magnetic coils, one for voltage (which may vary slightly and so must be measured) and one for current (which varies with the customer's electrical load). Volts (pressure) times amperes (flow) gives watts (power). The time enters in naturally, simply because the longer you wait, the more the hands advance. Watts (power) times time (hours) gives watt-hours (energy). Also, for the same amount of time, the more the load, the more the hands will advance. Either way, you pay. I hope one of these types is the type you are asking about.

Answer 2

An hour meter is a device used to track the number of hours that a machine or equipment has been in operation. It is commonly used in vehicles, generators, and other machinery as a way to monitor usage and schedule maintenance at regular intervals. This helps to ensure proper upkeep and longevity of the equipment.