4-20mA Signal Isolators

Acromag offers the industry’s best selection of 4-20mA signal isolators. Multi-channel 2-wire, 3-wire, and 4-wire isolators and isolated transmitters with AC, DC or loop-powered operation. Also offered is a loop-powered isolator with display (panel meter). Optical or galvanic isolation eliminate ground loop errors, reduce noise, and block high voltage transient surges. All Acromag isolators will withstand 1500V AC for 60 seconds and provide continuous 250V AC or 354V DC common-mode protection of your precious equipment. Acromag features solve many tough problems. Our multi-channel modules reduce costs and save space. Browse our selection below.

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    TT236: Current / milliVolt Input Two-Wire Transmitter

    • Multi-range ±20mA or ±500mV input
    • 4-20mA ouput (sink/source)
    • 12-32 V DC loop/local power
    The TT236 model is a space-saving two-wire transmitter that isolates and converts a DC current or low voltage input to a proportional 4-20mA control signal. A single unit supports both voltage and current input for extra flexibility. Power is received from the output loop current or a DC supply when using a three-wire connection. Click here to watch a short AcroMaggie video highlighting the TT230 Series.
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    TT336: Current/milliVolt Input, DC Power Transmitter

    • Multi-range ±20mA or ±500mV input
    • Universal current/voltage output
    • 12-32V DC power
    DC current and voltage output are both supported on a single model. An optional DIN rail bus can deliver primary or redundant power to multiple units without wiring. Click here to watch a short video highlighting the TT330 Series.  
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    Agility™ Config Tool (Tethered)

    • Tethered Agility™ Config Tool mobile application
    • For Acromag SP Series Signal Splitters and most TT Series Transmitters
    • Download available on Google Play for free.
    • Download Windows configuration software from the software tab below.
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4-20mA Signal Isolators Continued

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Signal Isolators For Signal Conditioning

As your I/O experts, Acromag is here to help! Below are three of our most popular application notes and whitepapers related to our signal isolators. Many times choosing the right isolator requires more than just comparing the number of channels and the cost per point. Find more application notes, white papers and support here: https://www.acromag.com/support/

Top 3 Ethernet Industrial Isolation Papers:

Some signal isolators are ideal for applications that require an isolator with a power supply in series with the output signal. Power is obtained from the output loop. The isolator must control current draw from the power supply in the output loop which is the 4-20mA signal. Since output and power share the same two wires, this type of isolator can be placed anywhere between the field sensing device and the PLC/DCS or monitoring device. Usually, the isolator is located close to the field device. Since both the input and output signal are 4-20mA, location of the device is not critical.

Other signal isolators are useful when adding and isolating a monitoring instrument to an existing current loop. When adding a field device such as a recorder or display, no additional power source is required for the added loop or for the isolator. The isolator's output is powered by the input loop power and drives passive loads only.