Black Box EME102A User Manual

4-20mA Converter

Introduction

The 4-20 mA signal converter is used to integrate the unit with a 4-20 mA transmitter. 4-20 mA
technology is used to communicate analog signals over long distances where electrical
interference is a problem. This solution is often used in the process control industry to collect the
analog values from a wide array of remote sensors. Current signals are much less susceptible to
noise than voltage signals. A voltage signal can be converted to current and then broadcast over
a long distance before it is converted back to voltage and read by the unit.
4-20 mA transmitters are common in the industry for use with high quality sensors. With the 4-20
mA converter, these sensors can now be integrated into the unit, enhancing their value with the
addition of graphing, web interface, email interface, thresholds, and limits.
The accuracy of our 4-20mA converters is 2%.
The resolution of our 4-20mA converters is 0.1mA.
You can use these figures in conjunction with your sensor's accuracy to find the
overall precision of your readings.
You can also calibrate the 4-20mA converter – see the Calibrate Sensors on
Individual Ports section of this manual for details.
One popular OID for the 4-20 mA Converters is the current reading. For a 4-20 mA Converter
plugged into RJ45#1 that OID is: .1.3.6.1.4.1.3854.1.2.2.1.17.1.3.0
Specifications & Features:
Electronics housed in small plastic case
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LED indicators on Converter show connection to unit
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Communications cable - RJ-45 jack to sensor using UTP Cat 5 wire.
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Power source: powered by the unit. No additional power needed.
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The unit auto detects the presence of the 4-20mA Converter
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Full autosense including disconnect alarm
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24 X 7 SUPPORT
info@blackbox.com – 724-746-5500 fax 724-746-0746
May 2009
4-20mA Converter Manual