Products › Torque Sensors › Static Torque Sensor (WTQ-120)
Static Torque Sensor (WTQ-120)
A reaction torque sensor measures torque on a stationary flange. It is bolted between a fixed frame and the device under test and reads the torque the casing reacts against, with no rotation and no slip rings. It suits torque-wrench calibration, motor and fastener bench tests, and any static torque check.
- Model: WTQ-120
- Range: 5 N·m to 200 N·m
- Type: keyed shaft, static (0 rpm)
- Mounting: two-end keyed shaft, in-line
- Accuracy: ±0.1 to ±0.3% FS
- Output: 1.0-1.5 mV/V bridge; 4-20 mA or 0-5/10 VDC optional
Overview
The WTQ-120 is a keyed-shaft static torque sensor. It couples in line through a keyed shaft at each end and reads static or holding torque from 5 to 200 N·m, without rotating.
It is the in-line static counterpart to a flange unit: where the flange torque sensor bolts face-to-face, the WTQ-120 sits in the shaft line on its keyed ends. It suits motor and gearbox bench work, stall and locked-rotor torque, valve and actuator holding torque, and other limited-rotation jobs. For the full static range and mounting options see the reaction torque sensors.
Features
What sets this reaction torque sensor apart on the bench:
Keyed shaft both ends
A keyed shaft at each end couples the sensor straight into the drive line.
Static (reaction)
Measures non-rotating torque, so there are no slip rings or bearings to wear.
5 to 200 N·m
Seven rated capacities for low to mid static torque.
Fast response
About 100 microseconds, for prompt static and holding-torque readings.
Strain-gauge bridge
A four-wire metal-foil bridge at 1.0-1.5 mV/V, with amplified output optional.
Overload protected
Safe to 150% and ultimate to 200% of full scale.
Working principle
The sensor is coupled in line through its keyed shaft ends and held against rotation. When torque is applied, the body twists slightly and strains a metal-foil bridge bonded inside it. Four strain gauges in a Wheatstone bridge turn that strain into a millivolt signal proportional to torque. Because it does not rotate, there are no slip rings or bearings, and the bridge responds in about 100 microseconds. An amplifier can convert the output to 4-20 mA or 0-5/10 VDC.
Technical specifications
| Parameter | Specification |
|---|---|
| Measuring principle | Keyed-shaft, reaction (static) strain-gauge bridge |
| Measuring range | 0-5 to 200 N·m (5 / 10 / 20 / 30 / 50 / 100 / 200 N·m) |
| Sensitivity | 1.0-1.5 mV/V |
| Non-linearity | ±0.1 / ±0.3% FS |
| Zero output | ±1% FS |
| Hysteresis | ≤±0.05% FS |
| Repeatability | ≤±0.05% FS |
| Creep | ≤±0.03% FS / 30 min |
| Response | about 100 microseconds |
| Temperature effect | 0.03% FS / 10 °C |
| Compensated temperature | -10 to 60 °C |
| Operating temperature | -20 to 65 °C |
| Input resistance | 350 or 750 ±10 ohm |
| Insulation resistance | ≥5,000 M-ohm / 100 VDC |
| Excitation | 10 VDC (9-15 VDC) |
| Safe overload | 150% FS |
| Ultimate overload | 200% FS |
| Output options | mV/V bridge; 4-20 mA or 0-5/10 VDC optional |
| Cable | 5.2 mm x 3 m |
| Material | Aluminum, stainless steel or alloy steel |
Models and ranges
Standard rated torques, keyed shaft, static:
| Rated torque | Type |
|---|---|
| 5 N·m | Keyed shaft, static |
| 10 N·m | Keyed shaft, static |
| 20 N·m | Keyed shaft, static |
| 30 N·m | Keyed shaft, static |
| 50 N·m | Keyed shaft, static |
| 100 N·m | Keyed shaft, static |
| 200 N·m | Keyed shaft, static |
Keyed shaft or flange
Pick the static sensor by how it mounts:
| Model | Mounting | Choose when |
|---|---|---|
| WTQ-120 keyed shaft | Two-end keyed shaft, in-line | Coupled into a shaft line for holding or stall torque |
| WTQ-9500 flange | Flange-to-flange, through bore | Low-profile inline reaction at a flange |
| MRT micro | Compact dual flange | Small torque (0.1 to 20 N·m), tight space |
For a spinning shaft see the rotary torque sensor; for the full static lineup see the reaction torque sensors.
Applications
- Motor and gearbox bench holding-torque tests
- Stall and locked-rotor torque measurement
- Valve and actuator holding torque
- Limited-rotation and clamping torque
- Static torque calibration setups
Challenge: A test bench had to measure torque up to 200 N·m on a drive that barely turned, around 0 to 20 rpm, close to static.
Solution: A keyed-shaft static torque sensor rated to 200 N·m, coupled in line on its keyed ends with a voltage output.
Result: The keyed shaft coupled straight into the bench drive, and the sensor read the near-static torque with no slip rings to wear.
Related products
FAQ
What is a static torque sensor?
It is a torque sensor that measures non-rotating torque. The WTQ-120 is a keyed-shaft static sensor that reads holding or stall torque from 5 to 200 N·m without turning, so it needs no slip rings.
What is the difference between a static and a rotary torque sensor?
A static (reaction) sensor is fixed and measures torque that does not rotate; a rotary sensor turns with the shaft and reads torque while it spins. Use static for held or slow torque, rotary for spinning shafts.
How does the WTQ-120 mount?
It couples in line through a keyed shaft at each end and is held against rotation, so the torque passes through the sensor body.
What torque range does the WTQ-120 cover?
Seven rated capacities from 5 to 200 N·m: 5, 10, 20, 30, 50, 100 and 200 N·m, all static.
What is another name for a torque sensor?
A torque sensor is also called a torque transducer, torque cell or moment sensor. A static one is a reaction torque sensor.
Request a quote
Tell us the torque range, the mounting style and the test, and we configure one reaction torque sensor for your bench, not a shelf part. Send the details and our engineers reply with a specification and quote.