six reasons isolators and splitters are a good choice
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04/12/23
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Types of IsolatorsTypes of Isolators
Output Loop Powered – 651T-0600
Input Loop Powered – 671T-0600
Self-Powered – 631T-0500
Steals powerfrom output loopw/ Sinking output
Steals powerfrom input loop
w/ Sourcing output
Separate Power Connection w/
Sourcing output
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Types of IsolationTypes of Isolation
Magnetic vs. Optical Isolation
An LED and a phototransistor are separated so that light may travel across a barrier but electrical current may not. As an electrical signal is applied to the input, photons are emitted from the LED which excite the phototransistor. When it activates, a proportional electrical signal is generatedat the output.
The primary and secondary coils are wrapped around a core of very high magnetic permeability such as iron. A current passing through the primary coil creates a magnetic field. The magnetic field lines pass through the iron core which produce a current in the output of the secondary coil.
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Reasons for Isolators / SplittersReasons for Isolators / Splitters
#1 – Prevent Ground Loops & Noise ProblemsA single ground poses no problem, but multiple grounds cause ground loops. In a ground loop, each ground is tied to a different earth potential. This allows current to flow between the grounds, interfering with the actual signal. If an extraneous current is produced from 50/60Hz AC power, noise is created. If this unwanted current is DC, it will create an offset.
An Isolator prevents unwanted currents by breaking ground loops. This eliminates noise problems and DC offsets.
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Reasons for Isolators / SplittersReasons for Isolators / Splitters
#2 – Isolate Bucking Power Sources
PLCH2S Analyzer / Monitor
4-20mA Sourced Output
Powered InputPassive Input
Loop Powered Output
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Reasons for Isolators / SplittersReasons for Isolators / Splitters
#3 – Amplification
Dewpoint Transmitter
AC Powered, 4-20mA Output up to 270 Ohms
Output Up to 1000 Ohms
Chart Recorder 250 Ohms Input Impedance
Panel Meter 100 Ohms Input Impedance
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Reasons for Isolators / SplittersReasons for Isolators / Splitters
#4 – Splitter for Isolating Loads
1000 feet
500 feet
2-wire Pressure
Transmitter
PLC
Display
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Reasons for Isolators / SplittersReasons for Isolators / Splitters
# 5 – Surge Protection
Flowmeter
Surge plus Isolation and Amplification
Field Instrument
Control Room
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Reasons for Isolators / SplittersReasons for Isolators / Splitters
#6 – Easy to Scale / Adjust Range
4-wire Optical Sensor
Optical InterfaceModify software to re-scale
One step Load-Trim Adjustment
+/-.75% Accuracy
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