1. A process variable transmitter for use in an industrial process control or monitoring system, comprising: a process variable sensor in the process variable transmitter having a process variable sensor output related to a process variable; an accelerometer in the process variable transmitter and which is separate from the process variable sensor coupled to the transmitter having an accelerometer output related to acceleration; output circuitry configured to provide an output related to the sensed process variable; and diagnostic circuitry configured to: determine a ratio between the process variable output and the accelerometer output; diagnose a condition in the process based upon the ratio of the process variable sensor output and the accelerometer output and responsively provide a diagnostic output indicative of a diagnostic condition in the process.