I am at refinery ( HART & FOUNDATION F-BUS base plant ) on training base have to going on tomorrow for calibration in process area for CV( control valve) with smart posioner & smart FLOW-Xmeter ,Level-Xmeter(DP type ) with wet leg, do anybody like to guide me wht step should taken during calibration ? plz help me i am just a fresh for this ..plz .my all honourable senior ..plz