Siemens Sitrans LR200, Quick Start Manual, Page: 13 / 276

Page EN-12 SITRANS LR200 (HART) – QUICK START MANUAL 7ML19985XC81
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English
• For wiring requirements:
N. America: See the connection drawings listed above, which can be
downloaded from the product page of our website at:
www.siemens.com/LR200.
Europe: Follow local regulations.
Australia: Follow local regulations.
International: Follow local regulations.
• Use appropriate conduit seals to maintain IP or NEMA rating.
• Recommended intrinsically safe barriers are listed under
Passive Shunt Diode Barriers
on page 12.
• Refer to Instructions specific to hazardous area installations on page 13 and the ATEX
certificate listed above.
Passive Shunt Diode Barriers
How to select a passive barrier for SITRANS LR200
To make sure that the barrier safety description is suitable for the LR200 Intrinsically Safe (IS)
input parameters, carry out the following calculations:
Re-e = max. end-to-end resistance of the barrier
Rloop = loop resistance (total of cable resistance plus e.g. sense resistance,
displays, and/or PLC inputs)
Vbarrier = value of any non-linear voltage drops due to the barrier
1) Determine the value for Re-e from the data sheet.
2) Calculate the total value for Rloop: by adding, for example, sense resistance, displays,
and/or PLC inputs.
3) Calculate Rworking = Re-e + Rloop.
Note:
Selecting a suitable PLC input module, power supply, or barrier requires knowledge
about Intrinsic Safety and the application. It is the responsibility of the installer to ensure that
the intrinsically safe installation complies with both the apparatus approval requirements and
the relevant national code of practice.
Note:
A well regulated supply voltage is required.
Manufacturer Part Number
MTL 787SP+ (Dual Channel)
MTL 7787P+ (Dual Channel)
Stahl 9001/01-280-100-10 (Single Channel)
Stahl 9002/01-280-110-10 (Dual Channel)