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In the 20 mV mode, the total resistance of the test object and the lines connected to it must amount to at least
200 mOhm. If this value is fallen short of, the measurement current becomes too high and the device outputs
an error (current transmitter overloaded!). As the resistance increases, the measurement current drops and
the measured results become more uncertain. (
Ι
min
= 1 mA,
Ι
max
= 100 mA)
*Error including measurement and linearization with respect to the DIN characteristic (range -
100 °C ... + 300 °C). The error of the temperature sensor is not included.
Analog output
•
Analog output of the measurement amplifier (with respect
to "-
Ι
" or analog ground). Error: 2.5 %, TC 80 ppm/K
•
10 V correspond to the maximum display value (except in
the 20 mV mode). Capacity: <= 0.2 mA
•
Output resistance:
<= 0.1
Ω
.
This output supplies the measurement signal (zero measurement - if active, cable-breakage test and measure-
ment "ON"). This function is not recommended in the 20 mV mode, as the value of the measurement current
is unknown here. As no specific current is used, only a part of the required information is available
5.1.3 Measurement errors
Error tolerances and influence variables (for the standard procedure)
Resistance measurement (display range of 2000 and 20000):
Range
Measured value
%
Conv.: Minimum
Digits
Conv.: Medium
Digits
Conv.: Standard
Digits
Conv.: Maximum
Digits
200 m
Ω
0.03
± 4
± 3
± 2.5
± 2
2
Ω
0.03
± 4
± 3
± 2.5
± 2
20
Ω
0.03
± 4
± 3
± 2.5
± 2
200
Ω
0.03
± 4
± 3
± 2.5
± 2
2 k
Ω
0.03
± 4
± 3
± 2.5
± 2
20 k
Ω
0.03
± 4
± 3
± 2.5
± 2
200 k
Ω
0.03
± 4
± 3
± 2.5
± 2
Temperature coefficient: 20 ppm/K Conv. = Conversion settings (see chapter 4.4.4.1)
20 mV mode
Resolution
Display ranges
Measured
value
%
Conv.:
Minimum
Digits
Conv.:
Medium
Digits
Conv.:
Standard
Digits
Conv.:
Maximum
Digits
2000
0.0
m
Ω
... 200.000 m
Ω
0.05
4
3
2.5
2
0.200
Ω
...
2.000
Ω
0.05
2.00
Ω
...
4.09
Ω
0.1
20000
0.00
0.2000
0.600
m
Ω
Ω
Ω
...
...
...
200.00
0.6000
4.099
m
Ω
Ω
Ω
0.05
0.05
0.10
4
3
2.5
2
Temperature coefficient: 20 ppm/K
Type
Error
TC
*Pt100 (without sensor type)
0.07 K
20 ppm/K of ohmic value
Ι
ca. 0.8 mA
U input
1.5 mV
25 ppm/K
R
E
> 100 k
Ω
Ι
input
3
µA
20 ppm/K
R
E
< 20
Ω
