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SITRANS LC500 – OPERATING INSTRUCTIONS
7ML19985GE04
Int
e
rc
onnect
ion
Interconnection
Wiring
Supply
The SITRANS LC500 uses a switched power supply circuit, which makes the most
efficient use of the available power present on the terminals. If the signal current is low,
(4mA), the terminal voltage will be high, and if the signal current is high, (20 mA), the
terminal voltage may be low, due to all the resistive elements in the loop, such as the
barrier and sense resistor.
WARNING:
• The DC input terminals shall be supplied from a source providing
electrical isolation between the input and output, in order to meet the
applicable safety requirements of IEC 61010-1.
• Observe the specifications of the examination certificate valid in your
country.
• Observe the laws and regulations valid in your country for electrical
installations in potentially explosive atmospheres.
• Ensure that the available power supply complies with the power supply
specified on the product nameplate and specified in the examination
certificate valid in your country.
• Dust-proof protection caps in the cable inlets must be replaced by
suitable screw-type glands or dummy plugs, which are appropriately
certified for transmitters with explosion-proof protection.
• The lid must not be opened in wet locations while the unit is powered.
(A wet location is a location where water or another conductive fluid
may be present and is likely to increase the risk of electric shock.)
Notes:
•
The transmitter is powered by the current loop and needs at least 9.5-13 Volt on
the terminals: 9.5 V at 22 mA or 12 V at 3.6 mA.
•
The maximum supply is 33 Volt. If the voltage is higher the device will shut down.
•
The loop-circuit will withstand voltages up to 250 Vac/Vdc without any damage.