Siemens LR200 Quick Start Manual page 13

• For wiring requirements:
N. America:
Europe:
Australia:
International:
• Use appropriate conduit seals to maintain IP or NEMA rating.
• Recommended intrinsically safe barriers are listed under
on page 12.
Instructions specific to hazardous area installations
• Refer to
certificate listed above.
Selecting a suitable PLC input module, power supply, or barrier requires knowledge
Note:
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.
Passive Shunt Diode Barriers
A well regulated supply voltage is required.
Note:
Manufacturer
MTL
MTL
Stahl
Stahl
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.
Page EN-12 SITRANS LR200 (HART) – QUICK START MANUAL
See the connection drawings listed above, which can be
downloaded from the product page of our website at:
www.siemens.com/LR200.
Follow local regulations.
Follow local regulations.
Follow local regulations.
Part Number
787SP+ (Dual Channel)
7787P+ (Dual Channel)
9001/01-280-100-10 (Single Channel)
9002/01-280-110-10 (Dual Channel)
Passive Shunt Diode Barriers
on page 13 and the ATEX
7ML19985XC81