A multimeter is the combination of a DC voltmeter, AC voltmeter, ammeter, and ohmmeter. Power off testing includes analog signature analysis, ohmmeter, LCR Meter and optical inspection. An instrument for measuring resistance is called an ohmmeter. To reduce this effect, a precision ohmmeter has four terminals, called Kelvin contacts. Micro-ohmmeters (microhmmeter or micro ohmmeter) make low resistance measurements. This type of ohmmeter suffers from two inherent disadvantages. Yet another Fairey designed and manufactured component was the Safety Ohmmeter.