Siemens SITRANS P DS III - Page 18

SITRANS P DS III (7MF4.33.. 7MF4.34.. 7MF4.35..)
18 A5E03434626-03, 06/2013
h
O
Upper filling level
Δp
ME
Full-scale value
h
V
Gland distance
ρ
Density of the measured medium in the container
p
Pressure
ρ '
Density of fluid in the
negative pressure line
corresponds to the prevailing temperature there
g
Acceleration due to gravity
The process connection on the negative side is a female thread
1
/
4
-18 NPT or an oval flange.
Lay the line for the negative pressure using a seamless steel tube 12 mm x 1.5 mm.
4
Connecting
4.1
Basic safety instructions
WARNING
Unsuitable cables and/or cable glands
Danger of explosion in hazardous areas.
● Only use suitable cables and cable glands complying with the requirements specified in Chapter "Technical data
(Page 35)".
● Tighten the cable glands in accordance with the torques specified in Chapter "Technical data (Page 35)".
● When replacing cable glands use only cable glands of the same type.
●
After installation check that the cables are seated firmly.
WARNING
Hazardous contact voltage in versions with 4-conductor extension
Danger of electrocution in case of incorrect connection.
●
Observe the instructions in the 4-conductor extension operating manual for the electrical connection.
See also
Technical specifications (Page 35)
WARNING
Improper power supply
Danger of explosion in hazardous areas as result of incorrect power supply, e.g. using direct current instead of alternating
current.
● Connect the device in accordance with the specified power supply and signal circuits. The relevant specifications can
be found in the certificates, in Chapter "Technical specifications (Page 35)" or on the nameplate.
WARNING
Unsafe extra-low voltage
Danger of explosion in hazardous areas due to voltage flashover.
●
Connect the device to an extra-low voltage with safe isolation (SELV).