Lower and upper
range-values:
setting using reference
pressure for devices
without display
On devices without a display, you can set the lower and upper-range values with the
reference pressure and an ammeter. The reference pressure should be near the lower
and upper range-values. The associated current value must be calculated using the
following equation:
I – Current value
p – Reference pressure is near lower
or upper range-values
p
LRV
– Pressure lower range-value
p
URV
– Pressure upper range-value
#
Key
Entry
1
Example: Set a pressure transmitter as
follows:
Lower range-value: p
LRV
= 0 bar and
Upper range-value: p
URV
= 1.0.
There are two reference pressures available:
Near to lower range-value p = 0.1 bar
Near to upper range-value p = 0.9 bar
2
Enter pressure near the lower range-value
e.g. 0.1 bar
3
Calculate the associated current value for the
applied reference pressure,
e.g. 0.1 bar equals 5.4 mA
4
Set the current value 5.4 mA by
pressing the +Z or –Z keys several
times
5
Enter pressure near the upper range-value
e.g. 0.9 bar
6
Calculate the associated current value for the
applied reference pressure,
e.g. 0.9 bar equals 18.4 mA
7
Set the current value 18.4 mA by
pressing the +S or –S keys several
times
Position calibration –
display only
(bias pressure)
If the
display
does not show zero after zero point adjustment (due to mounting position),
then you can correct the display value to zero by adopting the bias pressure acting
(depending on mounting position). The position calibration using a bias pressure does
not affect the current output.
– –
+ +
Z
S
– –
+ +
Z
S
– –
+ +
Z
S
– –
+
+
Z
S
1
2
3
+
+
Test
4…20 mA
R
i
max. 7
Ω
11.5…45 V DC
BA187Y43
#
Key
Entry
1
Correct display:
Press +Z and +S simultaneously
twice: The bias pressure acting is
adopted
2
Display bias pressure
:
Press +Z and +S simultaneously
once: The bias pressure entered is
shown briefly.
3
Delete bias pressure
:
Press –Z and –S simultaneously
twice: The bias pressure entered is
deleted.
– –
+
+
+
Z
S
– –
+
+
+
Z
S
– –
+
+
+
Z
S
I
4
=
+
•
−
−
mA
16 mA (p
p
)
(p
p
)
URV
LRV
URV
0...2 bar g
p
p
Bias
p+pBias
pe=0
BA187Y72
4 Local Operation
Cerabar S
18
Hauser