SITRANS T measuring instruments for temperature
Transmitters for rail mounting
SITRANS TW
four-wire system, universal, HART
3/41
Siemens FI 01 · 2010
3
Power supply
Universal power supply unit
115/230 V AC/DC or 24 V AC/DC
Tolerance range for power supply
• With 115/230 V AC/DC PSU
80 ... 300 V DC; 90 ... 250 V AC
• With 24 V AC/DC PSU
18 ... 80 V DC; 20.4 ... 55.2 V AC
(in each case interruption-resistant
up to 20 ms in the complete toler-
ance range)
Tolerance range for mains fre-
quency
47 ... 63 Hz
Power consumption with
• 230 V AC
≤
5 VA
• 230 V DC
≤
5 W
• 24 V AC
≤
5 VA
• 24 V DC
≤
5 W
Electrical isolation
Electrically isolated circuits
Input, output, power supply and
sensor fault/limit monitoring output
are electrically isolated from one
another. The HART interface is
electrically connected to the out-
put.
Working voltage between all electri-
cally isolated circuits
The voltage U
eff
between any two
terminals must not exceed 300 V
Measuring accuracy
Measurement error
• Error in the internal cold junction
≤
3 °C
±
0,1 °C/10 °C
(
≤
5.4 °F
±
0,18 °F/18 °F)
• Error of external cold junction ter-
minal 7NG3092-8AV
≤
0.5 °C
±
0,1 °C/10 °C
(
≤
0.9 °F
±
0.18 °F/18 °F)
• Digital output
See "Digital error"
• Analog output I
AN
or U
AN
≤
0.05 % of span in addition to
digital error
Influencing effects (referred to the
digital output)
Compared to the max. span:
• Temperature drift
≤
0.08 %/10 °C (
≤
0.08 %/18 °F)
≤
0.2 % in the range -10 ... +60 °C
(14 ... 140 °F)
• Long-term drift
≤
0.1 %/year
Influencing effects referred to the
analog output I
AN
or U
AN
Compared to the span:
• Temperature drift
≤
0.08 %/10°C (
≤
0.08 %/18 °F)
≤
0.2 % in the range -10 ... +60 °C
(14 ... 140 °F)
• Power supply
≤
0.05 %/10 V
• Load with current output
≤
0.05 % with change from
50 ... 650
Ω
• Load with voltage output
≤
0.1 % with change in load current
from 0 ... 10 mA
• Long-term drift (start-of-scale
value, span)
≤
0.03 %/month
Response time (
T
63
without electri-
cal damping)
≤
0.2 s
Electromagnetic compatibility
According to EN 61326 and
NAMUR NE21
Certificate and approvals
ATEX
To DIN EN 50014: 1997,
EN 50020: 1994
Intrinsic safety to EN 50 020
• for 7NG3242-x
A
xxx
II (1) G D [EEx ia/ib ] IIB
• for 7NG3242-x
B
xxx
II (1) G D [EEx ia/ib ] IIC
EC-Type Examination Certificate
TÜV (German Technical Inspec-
torate) 01 ATEX 1675
Rated conditions
Installation conditions
Location (for devices with explo-
sion protection)
• Transmitters
Outside the potentially explosive
atmosphere
• Sensor
Within the potentially explosive
atmosphere zone 1 (also in zone 0
in conjunction with the prescribed
protection requirements for the
sensor)
Ambient conditions
Permissible ambient temperature
-25 ... +70 °C (-13 ... +158 °F)
Permissible storage temperature
-40 ... +85 °C (-40 ... +185 °F)
Climatic class
• Relative humidity
5 ... 95 %, no condensation
Design
Weight
Approx. 0.24 kg (0.53 lb)
Enclosure material
PBT, glass-fibre reinforced
Degree of protection to IEC 529
IP20
Degree of protection to VDE 0100
Protection class I
Type of installation
35-mm top hat rail (1.38 inch)
(DIN EN 50022) or 32-mm G-type
rail (1.26 inch) (DIN EN 50035)
Electrical connection/process con-
nection
Screw plug connectors,
max. 2.5 mm² (0.01 inch²)
Parameterization interface
Protocol
HART, version 5.9
Load with connection of
• HART communicator
230 ... 650
Ω
• HART modem
230 ... 500
Ω
Software for PC/laptop
SIMATIC PDM version V5.1 and
later
© Siemens AG 2009
