Yokogawa EJA115 User Manual
Page 14
IM 01C22T02-01E
2-6
2. HANDLING CAUTION
• Process Temperature: 120
°
C max.
• Ambient Temperature: –40 to 60
°
C
Note 2. Installation
• All wiring shall comply with local installa-
tion requirements. (Refer to the installation
diagram)
Note 3. Maintenance and Repair
• The instrument modification or parts
replacement by other than authorized
representative of Yokogawa Electric Corpo-
ration is prohibited and will void KEMA
Intrinsically safe Certification.
Note 4. Special Conditions for Safe Use
• In the case where the enclosure of the
Pressure Transmitter is made of aluminium,
if it is mounted in an area where the use of
category 1 G apparatus is required, it must
be installed such, that even in the event of
rare incidents, ignition sources due to impact
and friction sparks are excluded.
᭹
FISCO Model
Non-Hazardous
Locations
Hazardous Locations
F0202.EPS
Terminator
(FISCO Model)
Ex i
Field Instruments
(Passive)
Hand-
held-
Terminal
Supply Unit and
Safety Barrier
(FISCO Model)
Terminator
Data
U
U
I
I.S. fieldbus system complying with FISCO
The criterion for such interconnection is that the
voltage (U
i
), the current (I
i
) and the power (P
i
), which
intrinsically safe apparatus can receive, must be equal
or greater than the voltage (U
o
), the current (I
o
) and the
power (P
o
) which can be provided by the associated
apparatus (supply unit).
P
o
Ϲ P
i
, U
o
Ϲ U
i
, I
o
Ϲ I
i
In addition, the maximum unprotected residual capaci-
tance (C
i
) and inductance (L
i
) of each apparatus (other
than the terminators) connected to the fieldbus line
must be equal or less than 5 nF and 10
H respec-
tively.
C
i
Ϲ 5nF, L
i
Ϲ 10H
Supply unit
The supply unit must be certified by a notify body as
FISCO model and following trapezoidal or rectangular
output characteristic is used.
U
o
= 14...17.5 V (I.S. maximum value)
I
o
based on spark test result or other assessment.
No specification of Lo and Co is required on the
certificate or label.
Cable
The cable used to interconnect the devices needs to
comply with the following parameters:
Loop resistance Rc: 15...150
Ω
/km
Inductance per unit length Lc: 0.4...1 mH/km
Capacitance per unit length Cc: 80...200 nF/km
Length of spur cable: max. 30 m (IIC and IIB)
Length of trunk cable: max. 1 km (IIC) or 5 km
(EEx ia IIB T4)
Terminators
The terminator must be certified by a Notified body as
FISCO model and at each end of the trunk cable an
approved line terminator with the following parameters
is suitable:
R = 90...102
Ω
C = 0...2.2
F (0.8...1.2 F is required in operation)
The resistor must be infallible according to IEC 60079-
11. One of the two allowed terminators might already
be integrated in the associated apparatus (bus supply
unit).
Number of Devices
The number of devices (max. 32) possible on a
fieldbus link depends on factors such as the power
consumption of each device, the type of cable used,
use of repeaters, etc.
᭹
Entity Model
Non-Hazardous
Locations
Hazardous Locations
F0203.EPS
Terminator
Ex i
Field Instruments
(Passive)
Hand-
held-
Terminal
Supply Unit and
Safety Barrier
Terminator
Data
U
U
I
I.S. fieldbus system complying with Entity model