The MTT MS3703 is a slim plug-in millivolt isolator, mounted on a plug-in base socket for quick swap-out without rewiring. It accepts a -200mV to +200mV DC input, with span from 5mV to 400mV (10mV minimum for negative signals), 1MΩ min input resistance, and a maximum continuous input of 30V DC.
Output is 0~20mA DC or 4~20mA DC, or a -10V to +10V DC range, available as a single output or an isolated dual output, with output load up to 750Ω for a single 4~20mA output. Zero and span are each adjustable by ±5% of span, with 4-way isolation between input, outputs, and power.
Accuracy is better than ±0.1% of span (at 25°C±5°C), with response time of 160ms max (0-90%). CMRR is 100dB minimum at 500V AC, with dielectric strength of 2000V AC for one minute – this is what keeps a low-level millivolt reading clean of ground loops and noise over a long cable run.
The unit mounts on wall or DIN rail via a plug-in socket base, with M3.5 screw terminals, weighing up to 120g for the main unit and 80g for the socket, with overall dimensions of 29mm × 86mm × 125mm. Power supply is flexible: 100-240V AC (50/60Hz), 24V DC, or 100-240V DC (approximately 4.0-6.0W depending on configuration).
| Input Range | -200mV to +200mV DC |
| Input Span | 5mV to 400mV (10mV minimum for negative signals) |
| Input Resistance | 1MΩ minimum |
| Maximum Input Voltage | 30V DC continuous |
| Output | 0-20mA DC or 4-20mA DC, or -10V to +10V DC range (single or isolated dual output) |
| Output Load | Up to 750Ω for a single 4-20mA output |
| Zero & Span Adjustment | ±5% of span |
| Isolation | 4-way isolation between input, outputs, and power |
| Power Supply | 100-240V AC (50/60Hz), 24V DC, or 100-240V DC (approx. 4.0-6.0W depending on configuration) |
| Accuracy | Better than ±0.1% of span (at 25°C±5°C) |
| Response Time | 160ms maximum (0-90%) |
| CMRR | Minimum 100dB at 500V AC |
| Dielectric Strength | 2000V AC for one minute |
| Dimensions (W x H x D) | 29mm x 86mm x 125mm |
| Weight | Main unit 120g; socket 80g |
| Mounting | Wall or DIN rail mounting, plug-in socket base |
| Terminals | M3.5 screw terminals |
| Operating Temperature | -5 to 55°C ambient (storage: -10 to 60°C) |
| Operating Humidity | 5-90% RH, non-condensing |
Frequently Asked Questions
What is the MTT MS3703 used for?
It converts a low-level millivolt DC signal — from a load cell, strain gauge, shunt, or similar source — into a standard 4-20mA, 0-20mA, or DC voltage output, with isolation to break ground loops.
Can the MS3703 be used with load cells and strain gauges?
Yes, as long as the output falls within its -200mV to +200mV input range. Tell us the load cell’s rated output (usually in mV/V) and its excitation voltage, and we can confirm compatibility.
What’s the difference between the MS3703 and the MS3701 / MS3702?
The MS3701 and MS3701F are thermocouple transmitters, and the MS3702 family is for RTD inputs. The MS3703 is for general millivolt DC sources that aren’t a thermocouple or RTD — load cells, shunts, or similar low-level signals.
Does the MS3703 provide excitation power for the sensor?
No — the MS3703 conditions and isolates an existing millivolt signal; it doesn’t supply excitation voltage. If your sensor needs its own excitation supply, let us know and we can check the right setup.
How do I know which MS3703 configuration I need?
Send us your source’s millivolt range, whether you need a single output or isolated dual output, and the output signal your PLC or DCS expects. We’ll confirm the right configuration before you order.
Download MTT MS3703 Slim Plug-In Millivolt Isolator information here
Spec Sheet: MTT MS3703 Spec Sheet
Manual: MTT MS3703 Manual
