Deltabar S
64
Hauser
Installation instructions
Instructions for diaphragm seal systems
• Hauser offer flushing rings as accessory to clean process isolating diaphragms without taking the
transmitters out of process.
For further information please contact your local Hauser Sales Center.
• The diaphragm seal together with the transmitter form a closed, calibrated system, which is filled through
ports in the diaphragm seal and in the measuring system of the transmitter. These ports are sealed and must
not be opened.
• In the case of devices with diaphragm seals and capillaries, the zero point shift caused by the hydrostatic
pressure of the filling liquid column in the capillaries must be taken into account when selecting the
measuring cell. If a measuring cell with a small measuring range is selected, the sensor nominal range can
be overdriven as a result of position adjustment.
See the following diagram and the following example.
• For devices with capillary a suitable fastening device (mounting bracket) is recommended.
• When using a mounting bracket, sufficient strain relief must be allowed for in order to prevent the capillary
bending down (bending radius
100 mm).
• The temperature and length of both capillaries should be the same when using two-sided diaphragm seal
systems.
Selecting the measuring cell (observe the hydrostatic pressure of the filling fluid column in the capillaries!)
P01-FMD78xxx-11-xx-xx-en-004
Pressure on the negative side of the differential pressure transmitter (p
–
) when the tank is empty (min. level)
Pressure on the positive side of the differential pressure transmitter (p
+
) when the tank is empty (min. level)
Differential pressure at the transmitter (
p
Transmitter
) when the tank is empty
+ –
+
–
max.
min.
Δ
H = 1 m
Hu = 0.2 m
Hv = 1.8 m
H1 = 0.3 m
= 1.0 kg/dm
ρ
M
3
p
i
= 0.96 kg/dm
ρ
Fl
3
Tank with water
Capillaries with silicone oil
= 197.77 mbar + p
= 1.8 m • 0.96 • 9.81 + 0.3 m • 0.96 • 9.81 + p
kg
dm
3
m
s
kg
dm
3
m
s
p = p + p
= Hv •
• g + H1 •
• g + p
ρ
ρ
H1
Fl
Hv
–
Fl
i
i
i
= 47.87 mbar + p
p = p + p
= Hu •
• g + H1 •
• g + p
ρ
ρ
M
H1
Fl
Hu
+
= 0.2 m • 1 • 9.81 + 0.3 m • 0.96 • 9.81 + p
kg
dm
3
m
s
kg
dm
3
m
s
i
i
i
