ZEN-LOG-MAN-16V03 (0930)
Copyright © 2016 Define Instruments
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The RTD (standing for Resistance Temperature Device) is highly stable
and accurate, and is fast becoming the most popular temperature
sensor in industry.Often referred to as Pt100 and Pt1000, the Pt repre-
sents platinum (the dominant metal in its construction), and 100/1000
is the resistance in ohms at 0°C.
Supported RTD types/ranges
Pt100/Pt1000 (0.02°F/0.01°C res)
-328 to 572°F (-200 to 300°C)
Pt100/Pt1000 (0.1°F/0.1°C res)
-328 to 1472°F (-200 to 800°C)
RTD 3 Wire
Pt100/1000
Connection Example for 3-Wire RTD
Inputs
3-Wire
Field RTD
Input
Channel
A
B
B
3-Wire
Field RTD
Input
Channel
A
B
B
3-Wire
Field RTD
Input
Channel
A
B
B
Note 1
All RTD inputs are isolated from
each other.
Note 2
All RTD cables must be screened,
with screen earthed at one end only. All
three wires must be the same resistance
(i.e. the same type and size).
Note 3
To minimise lead resistance errors,
3-wire RTD’s should be used. Offset errors
for 2-wire RTD’s may be compensated for
in the software.
Note 4
Do not run input cables in close
vicinity to noisy power supplies, contac-
tors or motor cables. The best practice is
to run input cables on a separate earthed
cable tray. This will minimise RFI effects,
of which magnitude cannot be easily
predicted.
7.3 - RTD input
RTD Pt100
3 wire RTD DIN 43760: 1980
RTD Pt1000
3 wire RTD standard
Resolution
-328–572°F (-200–300°C) = 0.02°F (0.01°C)
-328–1472°F (-200–800°C) = 0.1°F (0.1°C)
Lead resistance
10Ω/lead max
recommended
Sensor current
0.6mA continuous
Sensor fail
upscale
Accuracy
-328–572°F (-200–300°C) = ±0.1°C
-328–1472°F (-200–800°C) = ±0.3°C
Ambient drift
0.003°C/°C typical
