Before performing the checkout procedure:
Make sure that your bare hands do not come into contact with meter leads or segment wiring. The body acts as a capacitor and body contact with leads or wiring could result in false readings.
Some fieldbus segments with isolated couplers or barriers used in hazardous area applications may indicate a low resistance measurement for "+ to - " and/or a high capacitance measurement for "+ to - ". These readings can be acceptable providing that the fieldbus signal's waveform and voltage compare to that shown in the sample waveforms.