The MTT MS3765 Slim Plug-In Arithmetic Operation Unit takes two independent DC current or voltage signals and performs addition, subtraction, multiplication, or division on them, producing a single isolated output proportional to the result. Rather than dedicating separate modules to summing and differencing functions, the MS3765 consolidates all four basic arithmetic operations into one plug-in unit, giving panel designers a single part number that can be configured to whichever calculation the application calls for.
The operation to be performed, along with independent scaling factors for each input, is set directly on the module through front-panel UP/DOWN switches with an LED digit display, so technicians can select or change the equation on site without reprogramming a PLC. Front-accessible trimmers handle zero and span adjustment, and four-way galvanic isolation between inputs, outputs, and power keeps the calculated signal free of noise and ground-loop interference, making the MS3765 a flexible building block for ratio, blending, and comparison calculations at the panel level.
| Input Ranges | Current -100 to 100mA (200µA-200mA span); voltage -300 to 300V (400mV-600V span) |
| Input Resistance | 1MΩ min. (voltage); 10Ω-250Ω (current, varies by range) |
| Max Allowable Input | 30V DC max (voltage models); 40mA DC max (current models) |
| Input Bias | -100 to 100% |
| Output Ranges | Current 0-20mA (4-20mA span); voltage -10 to 10V (10mV-20V span) |
| Output Load | 750Ω max (single 4-20mA); 550Ω (Output 1) / 350Ω (Output 2) (dual) |
| Adjustment | ±5% of span, zero and span, via front trimmers |
| Selectable Operations | Addition, subtraction, multiplication, division — four selectable equations with independently programmable K1/K2 factors (0.10-2.00) |
| Accuracy | Addition/subtraction: ±0.2% of span (K1,K2 ≤1.00), ±0.4% (K1 or K2 >1.00); multiplication: ±0.2% (K1xK2 ≤1.00), ±0.4% (K1xK2 >1.00); division: ±1.0% (K1/K2 ≤1.00), ±2.0% (K1/K2 >1.00) |
| Temperature Effect | Better than ±0.15% of span per 10°C change |
| Response Time | 150ms max (0-90%, step input at 100%) |
| CMRR | 100dB min. (500V AC, 50/60Hz) |
| Isolation | Complete isolation between input, Output 1, Output 2, power, and ground; 100MΩ min. insulation resistance @500V DC; 2000V AC dielectric strength (1 minute), 500V AC (between outputs) |
| Power Supply | 100-240V AC (47-63Hz), 24V DC ±10%, or 100-240V DC; 1.7-6.0W single output / 2.1-7.2W dual output depending on supply type |
| Dimensions | W29 x H86 x D125mm (including mounting hardware) |
| Weight | 130g (main unit) / 80g (socket) max |
| Terminals | M3.5 screw terminal with power terminal block cover, 0.8-1.0 Nm torque |
| Mounting | Wall or DIN rail mount |
| Operating Conditions | -5 to 55°C, 5-90% RH non-condensing |
| Storage Temperature | -10 to 60°C |
| Additional Features | Front-panel UP/DOWN switches with 8.0mm LED digit display for setting equation and factors |
Frequently Asked Questions
What is the MTT MS3765 used for?
It takes two independent DC current or voltage signals and performs addition, subtraction, multiplication, or division on them, producing a single isolated output proportional to the result. Instead of dedicating separate modules to summing and differencing functions, the MS3765 consolidates all four basic arithmetic operations into one plug-in unit.
How is the MS3765 different from the MS3761 adder or MS3762 subtractor?
The MS3761 and MS3762 are fixed to one operation each, add or subtract. The MS3765 can be configured for any of the four operations, addition, subtraction, multiplication, or division, on the same hardware, which simplifies stocking when you’re not sure in advance which calculation a given application will need.
How is the operation and weighting configured?
The operation (add, subtract, multiply, divide) is selected on the unit, along with independently programmable K1/K2 scaling factors on each input, so the two signals can be weighted before the calculation is performed.
What input and output signal types does it accept?
Input accepts current (-100 to 100mA) or voltage (-300 to 300V), and output is a standard 0-20mA current or -10 to 10V voltage span, single or dual. Tell us your two input signal types and the operation you need, and we can confirm the setup.
How do I know if the MS3765 is right for my application?
If you need to combine two DC signals with any of the four basic arithmetic operations, whether that’s a sum, a difference, a ratio, or a product, the MS3765 covers it in one part. Send us your two input signal types and which calculation you need and we can confirm before you order.
Download MTT MS3765 Slim Plug-In Arithmetic Operation Unit information here
Spec Sheet: MTT_SpecSheet1_MS3765_Rev230_E
Manual: MTT_Manual1_MS3765_Rev140_E
