FD Maximum pressure limiters for liquid gas installations

FD Maximum pressure limiters for liquid gas installations are constructed in accordance with the special directives for liquid gas engineering. All parts coming into contact with the medium are made of stainless steel 1.4104 and 1.4571. The pressure sensor was designed to be "self-monitoring", i. e. should the measuring bellows rupture, the pressure sensor switches off towards the safe side. The pressure sensor thus complies with "of special construction" in the sense of VdTÜV Memorandum "Pressure 100". Pressure limiters are used in intrinsically safe control circuits (Ex-protection Ex-i). By using an isolating amplifier, the control circuit is also monitored for line break and short circuit.It comes with a switch housing made of Die cast aluminium GD Al Si 12. Switching pressure (3-16 bar) is adjustable with the setting spindle after removing the terminal box.Explosion protection Ex-i types (only when used in conjunction with isolating amplifier).Please note: FD pressure limiters must never be connected directly to mains voltage.They must only be used in conjunction with isolating amplifier.Interlock after cutout :Internal interlock on FD16–327.Interlock defeat: after pressure reduction ofapprox. 2.5 bar by pressing the red button (withtool) on the scale side of the pressure switch.External interlock on FD16–326.Interlock defeat: After pressure reduction ofapprox. 0.5 bar. Press unlocking button incontrol cabinet.

• Line break and short circuit monitoring: On types FD16–326 and FD16–327 used inconjunction with isolating amplifier, the control circuit is monitored for short circuit and line break.
• The resistor combination incorporated into the pressure switch ensures that a defined current flows at all times during normal operation.
• In the event of short circuit or line break, the current level changes and the relaydrops out to the safe side.

• ID 0000033127 according VdTUEV Memorandum Pressure 100/1, Issue 07.2006 and DIN EN 12952-11, Issue 09.2007 and DIN EN 12953-9, Issue 09.2007
• 01 202 931-B-11-0002 according Directive 97/23/EC
• SIL2 according IEC 61508-2