The MTT MS3903 Chassis-mounting Millivolt Isolator takes a low-level DC millivolt signal and converts it into a standard isolated DC output, packaged in the same compact chassis-mount format as the rest of the MS39-series for high-density panel installations. Rather than mounting on a DIN rail, it plugs into an RC3900 chassis base alongside other chassis-mount modules, making it a space-efficient choice where many signal channels need to be conditioned in a small footprint.
Input ranges from 0-10mV up to 0-100mV, plus bipolar and custom spans, cover the common low-level sensor signals that need isolating and scaling before they reach a controller. Two independently configurable outputs are available in various current and voltage combinations, front-accessible trimmers allow zero and gain adjustment, and mutual isolation between input, both outputs, and power keeps each channel electrically independent. Anti-humidity PCB coating helps the MS3903 hold up in demanding panel environments.
| Input Signal Options | 0-10mV, 0-100mV, ±10mV, ±100mV DC, or custom 5-200mV |
| Input Resistance | 1MΩ min. |
| Max Allowable Voltage | 30V DC continuous |
| Output Options | Dual outputs, combinations of 1-5V, 0-5V, 0-10V, ±5V, ±10V DC, or mixed voltage/current (1-5V/4-20mA) |
| Output Load | 2mA max (voltage); 300Ω max (current) |
| Adjustment | ±2% of span, zero and gain, via front trimmers |
| Accuracy | ±0.1% full scale at 25°C±5°C; ±0.2% of span per 10°C temperature drift |
| Response Time | 160ms max (0-90%, 100% step input) |
| CMRR | 100dB min. (500V AC, 50/60Hz) |
| Isolation | Mutual isolation across input, both outputs, and power; 100MΩ min. insulation resistance @500V DC; 1500V AC dielectric strength (input to other ports), 500V AC (between outputs/power) |
| Power Supply | 24V DC ±10%, 50mA max; 300mA fuse standard |
| Dimensions | W19.5 x H53 x D84mm |
| Weight | Approx. 70g |
| Mounting | Chassis mount on RC3900-series mounting base |
| Operating Conditions | 0-55°C, ≤90% RH non-condensing |
| Storage Temperature | -10 to 60°C |
| Additional Features | Anti-humidity PCB coating (HumiSeal 1A27NS polyurethane); optional response frequency/time customization |
Frequently Asked Questions
What is the MTT MS3903 used for?
It takes a low-level DC millivolt signal and converts it into a standard isolated DC output, in the same chassis-mount format as the rest of the MS39-series for high-density panel installations on an RC3900 base.
What input ranges does it support?
0-10mV up to 0-100mV, plus bipolar and custom spans. Tell us your sensor’s millivolt output range and we can confirm the configuration.
Can I get dual outputs from one unit?
Yes, two independently configurable outputs are available in various current and voltage combinations, with mutual isolation between input, both outputs, and power keeping each channel electrically independent.
Why chassis-mount instead of a DIN-rail module?
The MS3903 plugs into an RC3900 chassis base alongside other chassis-mount modules, making it a space-efficient choice where many millivolt signal channels need to be conditioned in a small panel footprint.
How do I know if the MS3903 is right for my application?
If you have a low-level millivolt signal that needs isolating and scaling in a high-density, chassis-mounted panel, the MS3903 on an RC3900 base covers that. Send us your input range and desired output signal and we’ll confirm before you order.
Download MTT MS3903 Chassis-mounting Millivolt Isolator information here
Datasheet: MTT_MS3903_Datasheet
