Fema I4 Series, Manual

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SERIES I4 · Model I4P
Section INDUSTRIAL . ISOLATED SIGNAL CONVERTERS
www.fema.es 11
11.6 Pt100 sensors and other Pt
MEASURING PT TEMPERATURE SENSORS
The instrument can be configured to measure temperature
from Pt100, Pt500 and Pt1000 sensors. See connections at
‘Table 27’.
PREDEFINED CONFIGURATION CODES
See ‘Table 28’ and ‘Table 29’ for a list of predefined input-output
configuration codes. To activate a code see section 13.1.
CUSTOMIZED SIGNAL RANGES
To customize the input and / or output signal ranges, access the
‘ Advanced scaling ’ menu (see section 13.6).
SENSOR BREAK DETECTION AND SHORT CIRCUIT DETECTION
The instrument detects the sensor break or short circuit error at the
input signals, and displays an error message (see section 16).
PT100 WITH 2 AND 3 WIRES
The instrument accepts 2 and 3 wire Pt100 sensor. When using 3 wires,
the instrument applies automatic compensation of the cable resistance
up to 15 Ohms. All three terminals must be connected (see Table 27).
‘ALPHA’ TEMPERATURE COEFFICIENT
The instrument is configured by default, to work with an ‘alpha’ value
of ‘0.0385’ for Pt sensors (Pt100, Pt500, Pt1000). To activate an ‘alpha’
value of ‘0.0390’ see section ‘13.4’. This parameter is associated to the
sensor and depends on the sensor manufacturer.
CURRENT THROUGH THE SENSOR
The instrument generates 960 uA through Pt100 sensors, <170 uA
through Pt500, and <120 uA through Pt1000 sensors.
OUTPUT SIGNAL
The output signal is configurable to 4/20 mA (active and passive) and
0/10 Vdc.
11. Input signals (cont.)
Table 27 | Connection examples for Pt100 (2 and 3 wires) and Pt500, Pt1000
1 2 3
Pt100-
Pt100+
Pt100- (3
rd
wire)
Connections for Pt100 (3 wires)
Pt100-
1 2 3
(shortcircuit 1-2)
Pt100+
Connections for Pt100 (2 wires)
1 2 3
Pt-
Pt+
Connections for Pt500 and Pt1000 (2 wires only)
Pt
Temperature
Table 28 | Temperature ranges for Pt100
Input
signal
Code for
4/20 mA output
Code for
0/10 Vdc output
Measurement range Total error
(error en ºC)
Pt100
070 170 -200/850 ºC -328/1562 ºF <0.25% FS
(<2.6 ºC)
071 171 0/600 ºC 32/1112 ºF
<0.25% FS
(<1.5 ºC)
072 172 0/400 ºC 32/752 ºF
<0.30% FS
(<1.2 ºC)
073 173 0/300 ºC 32/572 ºF
<0.25% FS
(<0.8 ºC)
074 174 0/200 ºC 32/392 ºF
<0.30% FS
(<0.6 ºC)
075 175 0/100 ºC 32/212 ºF
<0.50% FS
(<0.5 ºC)
076 176 -50/+50 ºC -58/122 ºF
<0.50% FS
(<0.5 ºC)
Table 29 | Temperature ranges for Pt500 and Pt1000
Input
signal
Code for
4/20 mA output
Code for
0/10 Vdc output
Measurement range Total error
Pt500 080 180 -200/850 ºC -328/1562 ºF <0.20% FS
Pt1000 081 181 -200/850 ºC -328/1562 ºF <0.20 % FS