The MTT MS3717 is a slim plug-in distributor that both powers a 2-wire loop transmitter and linearizes its output in one unit. It supplies the loop voltage the transmitter needs, reads its 4-20mA signal, extracts the square root, and passes on a clean, isolated DC output. That combination makes it a natural fit for differential-pressure flow measurement, where a pressure transmitter on an orifice plate or venturi produces a signal that rises with the square of flow rate; the MS3717 turns that curve into a straight line so downstream displays and controllers can read flow directly.
Like the rest of the plug-in transmitter series, the MS3717 clips into its own socket base for fast swap-out during calibration or maintenance without disturbing the field wiring, and a second isolated output is available for feeding an independent monitoring or logging system. Flexible AC or DC power plus wall or DIN rail mounting make it easy to fit into an existing panel.
| Input | 4-20mA DC from a 2-wire transmitter |
| Input Resistance | 250Ω |
| Transmitter Power Supply | 25V typical at 0% input; 18V typical at 100% input |
| Short-Circuit Protection | 26mA typical limit current |
| Output | 0-20mA or 4-20mA DC current, or 10mV to 20V DC voltage; single or dual isolated output |
| Output Load | 750Ω max. (4-20mA single output) |
| Accuracy | Better than ±0.2% of span (1-100% input, at 25°C±5°C) |
| Response Time | 85ms max. (0-90%, step input at 100%) |
| Temperature Effect | ±0.2% of span per 10°C change |
| CMRR | 100dB min. (500V AC, 50/60Hz) |
| Isolation | 4-way isolation between input, output 1, output 2, and power |
| Insulation Resistance | 100MΩ min. at 500V DC |
| Dielectric Strength | 2000V AC for 1 minute |
| Power Supply | 100-240V AC (50-60Hz), 24V DC (±10%), or 100-240V DC |
| Power Consumption | 7.5VA max. (AC), 2.4-2.9W max. (24V DC) |
| Dimensions | W29 × H86 × D125mm |
| Weight | 120g max. (main unit), plus 80g max. socket |
| Mounting | Wall or DIN rail mounting |
| Terminals | M3.5 screw terminals, 0.8-1.0 Nm torque |
| Operating Temperature | -5 to 55°C |
| Operating Humidity | 5 to 90% RH, non-condensing |
Frequently Asked Questions
What is the MTT MS3717 used for?
It powers a 2-wire loop transmitter and linearizes its signal in one unit. It’s most often paired with a differential pressure transmitter on an orifice-plate or venturi flow measurement, where the DP signal rises with the square of flow rate; the MS3717 extracts the square root so the output tracks flow rate directly.
Does the MS3717 supply loop power to the transmitter?
Yes — it supplies the loop voltage a 2-wire 4-20mA transmitter needs (typically 25V at 0% input, 18V at 100% input), so no separate power supply for the transmitter is required.
Do I need the square-root version, or the standard MS3707 distributor?
If your transmitter’s signal is already linear (most modern transmitters), the standard MS3707 distributor is enough. Use the MS3717 only when the transmitter’s raw signal is still in its squared, nonlinear form and needs linearizing, such as an older DP flow transmitter without built-in square-root extraction.
Can the MS3717 provide two separate outputs?
Yes — a second isolated output is available, so the linearized signal can feed a controller and a separate monitoring or logging system at the same time.
How do I know if the MS3717 is right for my application?
Send us your transmitter’s output signal and whether it’s already linearized, and we can confirm whether you need the MS3717 or a standard distributor.
Download MTT MS3717 Slim Plug-In Distributor (with Square-Root Extraction Function) information here
Spec Sheet: SpecSheet1_MS3717_Rev240.pdf
Manual: Manual1_MS3717_Rev140_E.pdf
