5 Connecting.................................................................................................................................................37
5.1 Basic safety instructions.........................................................................................................37
5.2 Connecting the device............................................................................................................41
5.2.1 Opening the device................................................................................................................41
5.2.2 Connecting the device............................................................................................................42
5.2.3 Closing the device..................................................................................................................43
6 Commissioning...........................................................................................................................................45
6.1 Basic safety instructions.........................................................................................................45
6.2 Switching on the supply voltage.............................................................................................46
6.3 Commissioning the device.....................................................................................................47
6.4 gauge pressure, absolute pressure from the differential pressure series and absolute
pressure from the gauge pressure series..............................................................................47
6.4.1 Commissioning for gases.......................................................................................................47
6.4.2 Commissioning with steam or liquid.......................................................................................49
6.5 Differential pressure and flow rate.........................................................................................50
6.5.1 Commissioning in gaseous environments..............................................................................50
6.5.2 Commissioning for liquids......................................................................................................52
6.5.3 Commissioning with vapor.....................................................................................................53
7 Service and maintenance...........................................................................................................................57
7.1 Basic safety instructions.........................................................................................................57
7.2 Cleaning.................................................................................................................................58
7.2.1 Servicing the remote seal measuring system........................................................................58
7.3 Maintenance and repair work.................................................................................................58
7.3.1 Defining the maintenance interval..........................................................................................59
7.3.2 Checking the gaskets.............................................................................................................60
7.3.3 Diagnostics messages...........................................................................................................61
7.4 Return procedure...................................................................................................................61
7.5 Disposal.................................................................................................................................61
8 Technical data............................................................................................................................................63
8.1 Input.......................................................................................................................................63
8.1.1 Gauge pressure.....................................................................................................................63
8.1.2 Gauge pressure with front-flush diaphragm...........................................................................64
8.1.3 Gauge pressure from the differential pressure series............................................................65
8.1.4 Absolute pressure from the gauge pressure series...............................................................66
8.1.5 Absolute pressure with front-flush diaphragm........................................................................67
8.1.6 Absolute pressure from the differential pressure series.........................................................68
8.1.7 Differential pressure and flow.................................................................................................69
8.1.8 Level.......................................................................................................................................70
8.2 Measuring accuracy of SITRANS P320.................................................................................71
8.2.1 Reference conditions.............................................................................................................71
8.2.2 Effect of auxiliary power supply..............................................................................................71
8.2.3 Gauge pressure.....................................................................................................................71
8.2.4 Gauge pressure from the differential pressure series............................................................73
Table of contents
SITRANS P320/P420 with 4 to 20 mA/HART
4 Compact Operating Instructions, 09/2018, A5E38874562-AB