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SITRANS LR250 (FF) – QUICK START MANUAL
7ML19985XN82
mm
mm
m
E
n
glis
h
FISCO Concept
Under the FISCO evaluation concept, SITRANS LR250 has the following characteristics:
The FISCO Concept allows interconnection of Intrinsically Safe apparatus to associated
apparatus not specifically examined in such combination. The criteria for interconnection is
that the voltage (Ui or Vmax), the current (Ii, or Imax) and the power (Pi, or Pmax) which
Intrinsically Safe apparatus can receive and remain Intrinsically Safe, considering faults, must
be equal to or greater than the voltage (Uo or Voc or Vi), the current (lo or Isc or li), and the
power (Po or Pmax) levels which can be delivered by the associated apparatus, considering
faults and applicable factors. In addition, the maximum unprotected capacitance (Ci) and
inductance (Li) of each apparatus (other than the termination) connected to the fieldbus must
be less than or equal to 5 nF and 10
μ
H respectively.
In each segment only one active device, normally the associated apparatus, is allowed to
provide the necessary energy for the fieldbus system. The allowed voltage Uo (or Voc or Vt) of
the associated apparatus is limited to the range of 14V dc to 24V dc. All other equipment
connected to the bus cable has to be passive, meaning that they are not allowed to provide
energy to the system, except for a leakage current of 50
μ
A for each connected device.
Separately powered equipment needs a galvanic isolation to assure that the Intrinsically Safe
fieldbus circuit remains passive.
2.Non-Sparking/Energy Limited wiring
• For wiring requirements: follow local regulations.
• Approved dust-tight and water-tight conduit seals are required for outdoor NEMA 4X /
type 4X / NEMA 6, IP67, IP68 locations.
(input voltage) U
i
= 17.5 V
(input current) I
i
= 380 mA
(input power) P
i
= 5.32 W
(internal capacitance) Ci
= 0
(internal inductance) Li
= 0
Note: For complete details and instructions regarding the FISCO Concept The FM/CSA
connection drawing number A5E02358161 can be downloaded from the product page of our
website at: www.siemens.com/LR250. Go to More Info > Installation Drawings > Level
Measurement > SITRANS LR250.
SITRANS LR250
Made in Canada
Siemens Milltronics Process Instruments Inc., Peterborough
7MLxxxx-xxxxx-xxxx
Encl.: NEMA / TYPE 4X, 6, IP67, IP68
Amb.Temp.: – 40 °C to 80 °C
Power Rating: 32 V
Max., 20 mA
Serial No: GYZ / A1034567
Warning:
Potential Electrostatic Charging Hazard Do Not Clean
Probe With A Dry Cloth.
Do Not Install Where Build-Up Of Charge Is Likely.
Use Cable Rated > 90°C
3 G
II
SIRA 09ATEX4354X
EEx nL IIC T4 Gc
FNICO:
Ui = 17.5 V
Ii = 570 mA
Pi = 7.98 W
Ci < 5 nF
Li < 20 µH
Entity:
Ui = 32 V
Ci < 5 nF
Li < 20 µH
EEx nA II T4 Gc
Un = 32 V
s
FOUNDATION FIELDBUS
The ATEX certificate listed on the nameplate
can be downloaded from the product page of our website at: www.siemens.com/LR250.
Go to More Info > Installation Drawings > Level Measurement > SITRANS LR250.
