There are intermittent "Communication Fail" alarms for certain transmitters configured as HART input in Delta V DCS. Physical wiring , grounding was checked and nothing major abnormality found. Can someone advise what else can be checked? what is causing these intermittent communication failure? Though there is no break in real time trend of process value, will it affect the signal? In DeltaV signal is configured as "Field Value Pct". Thanks