Yokogawa Wireless Temperature Transmitter YTA510 User Manual
Page 52
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<8. Handling Caution>
8-12
IM 01C50T02-01E
Supply unit
Trapezoidal or rectangular output characteristic only
Uo = 14...24 V (I.S. maximum value)
Io according to spark test result or other
assessment, e.g. 133 mA for Uo = 15 V (Group
IIC, rectangular characteristic) No specification
of Lo and Co in the certificate and on the label.
Cable
The cable used to interconnect the devices needs
to comply with the following parameters:
loop resistance R’: 15...150 Ω/km
inductance per unit length L’: 0.4...1 mH/km
capacitance per unit length C’: 80...200 nF/km
C’ =C’ line/line+0.5 C’ line/screen, if both lines
are floating
or
C’ =C’ line/line+C’ line/screen, if the screen is
connected to one line
length of spur cable: max. 30 m (Group IIC) or
120 m (Group IIB)
length of trunk cable: max. 1 km (Group IIC) or
1.9 km (Group IIB)
Terminators
At each end of the trunk cable an approved line
terminator with the following parameters is suitable:
R = 90...100 Ω
C = 0...2.2 F
The resistor must be infallible according to IEC
60079-11. One of the two allowed terminators
might already be intergrated in the associated
apparatus (bus supply unit)
System evaluations
The number of passive device like transmitters,
actuators, hand held terminals connected to
a single bus segment is not limited due to I.S.
reasons.
Furthermore, if the above rules are respected, the
inductance and capacitance of the cable need not
to be considered and will not impair the intrinsic
safety of the installation.
SAFE AREA
HAZARDOUS AREA
F0811.ai
Terminator
(FISCO Model)
Ex i
Field Instruments
(Passive)
Hand-
held-
Terminal
Supply Unit
(FISCO Model)
Terminator
Data
U
U
I
I.S. fieldbus system complying with FISCO
model
Installation Diagram for Type of
protection“n”
Non Hazardous Location
(*)‘C’ and ‘–’ may be shorted.
Hazardous Location
F0812.ai
Terminator
IEC Certified
[nL] Equipment
Temperature
Transmitter
Terminator
+
–
Transmitter
+
–
Transmitter
+
–
1
2
3
4
5
SUPPLY
C(*)
+
–
+
–
SENSOR