Teledyne NALL Manuale Utente

Pagina di 23
Manual 111-082010_Nall Mass Flowmeters 
Page 10 of 23 
 
4.4.3 
Electrical Zero Check 
Turn the power supply “ON” and allow the flowmeter 30 minutes to warm up.  Stop all flow through the 
transducer and check the electrical zero. 
CAUTION: 
DO NOT ASSUME THAT ALL METERING VALVES WILL COMPLETELY 
SHUT OFF FLOW.  EVEN A SLIGHT LEAKAGE THROUGH A VALVE WILL CAUSE AN 
INDICATION ON THE METER WHICH WILL FALSELY APPEAR TO BE A ZERO SHIFT. 
If necessary, adjust the “ZERO” potentiometer located on the front panel of the power supply, until the 
meter indicates zero.