Fema I4 Series, Manual

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SERIES I4 · Model I4P
Section INDUSTRIAL . ISOLATED SIGNAL CONVERTERS
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11.3 Resistances
MEASURING RESISTANCES
The instrument can be configured to measure resistance
signals with ranges from 1 Kohm up to 1 MOhm.
Measurement uses 2 wires. See connections at ‘Table 13’.
PREDEFINED CONFIGURATION CODES
See ‘Table 14’ 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
The instrument detects the sensor break and displays an error message
(see section 16).
CURRENT THROUGH THE SENSOR
The instrument generates a fixed current to measure the resistance
values.
MAXIMUM OVERSIGNAL AND PROTECTIONS
Active signals are not to be connected to the resistance input terminals.
Maximum active input is 3 Vdc. Higher voltage inputs will be internally
shorted and can be destructive.
OUTPUT SIGNAL
The output signal is configurable to 4/20 mA (active and passive) and
0/10 Vdc.
11. Input signals (cont.)
11.4 NTC sensors
MEASURING NTC SENSORS
The instrument can be configured to measure temperature
from common NTC sensors. Accepts standard NTC models
44004, 44005, 44006, 44007, 44008, 44030, 44031, 44032,
44033 and 44034. See connections at ‘Table 15’.
An independent range exists for NTC sensors characterized by its R
25
and
β parameters. Configurable R
25
values from 1.0 KOhm to 200.0 KOhm,
and β values from 2500 to 5500. This type of NTC can read signals down
to 0 Ohms and up to 16 MOhms.
PREDEFINED CONFIGURATION CODES
See ‘Table 16’ 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
The instrument detects the sensor break and displays an error message
(see section 16).
CURRENT THROUGH THE SENSOR
The instrument generates a maximum of 167 uA through the NTC
sensors, with a power dissipation of <10 uW.
OUTPUT SIGNAL
The output signal is configurable to 4/20 mA (active and passive) and
0/10 Vdc.
Table 13 | Connection examples for resistance signals
1 2 3
res+
res-
Table 14 | Input signal ranges for resistances
Input
range
Code for
4/20 mA output
Code for
0/10 Vdc output
Accuracy
(% FS)
Current on
resistance
Max.
overvoltage
0/1 KOhm 014 114 <0.20 % 167 uA 3 Vdc
0/10 KOhm 015 115 <0.20 % 45 uA 3 Vdc
0/100 KOhm 016 116 <0.20 % 4.5 uA 3 Vdc
0/1000 KOhm 017 117 <0.50 % 1 uA 3 Vdc
Table 15 | Connection examples for NTC signals
1 2 3
ntc+
ntc -
Table 16 | Input signal ranges for NTC sensors
Sensor Measurement range
Code for
4/20 mA output
Code for
0/10 Vdc output
Accuracy
(% FS)
Ntc 44004 -80/120 ºC -112/248 ºF 020 120 <0.30 %
Ntc 44005 -80/120 ºC -112/248 ºF 021 121 <0.25 %
Ntc 44006 -80/120 ºC -112/248 ºF 022 122 <0.10 %
Ntc 44007 -80/120 ºC -112/248 ºF 023 123 <0.15 %
Ntc 44008 -80/120 ºC -112/248 ºF 024 124 <0.20 %
Ntc 44030 -80/75 ºC -112/167 ºF 025 125 <0.10 %
Ntc 44031 -80/75 ºC -112/167 ºF 026 126 <0.10 %
Ntc 44032 -80/75 ºC -112/167 ºF 027 127 <0.20 %
Ntc 44033 -80/75 ºC -112/167 ºF 028 128 <0.10 %
Ntc 44034 -80/75 ºC -112/167 ºF 029 129 <0.10 %
Ntc R
25
=10K,
β
=3500 -50/90 ºC -58/194 ºF
030 130 <0.20 %
Resistances
NTC
Temperature