TQ401

Supported Applications

The TQ401 Series is a family of reaction torque cells engineered for demanding industrial environments. A stainless steel case, shielded cable, and heavy-duty surface key mount combine to deliver a rugged, non-slip connection that holds up in production and test settings. The surface key mount resists rotation under load, making the series well suited to reaction torque measurement on fixtures, gearboxes, fastening tools, and other rotating-restraint applications.

Each sensor ships complete with a 5-point calibration and carries a NIST Standard traceable reference, so units are ready for accurate service on arrival. The cells are RoHS compliant, and each is compatible with process meters such as the DP41-S and DP25B-S for readout and control.

Operating Conditions & Performance

The TQ401 Series delivers high-accuracy reaction torque measurement with an accuracy class of ±0.2% FSO and matching linearity of ±0.2% FSO. Repeatability is held to ±0.05% FSO, hysteresis to ±0.1% FSO, and zero balance to ±2% FSO, supporting reliable, reproducible readings across the load cycle.

The bridge provides a rated output of 2 mV/V with a recommended excitation of 10 Vdc, 15V maximum. Input resistance is 360 Ω minimum and output resistance is 350 ±5 Ω. Thermal effects are minimal, specified at ±0.005% FSO/°F on zero and ±0.005% rdg/°F on span.

The cells operate over an ambient range of -54 to 107°C, with a compensated temperature range of 16 to 71°C for best accuracy. Mechanical robustness includes a safe overload of 150% of capacity and an ultimate overload of 300% of capacity. The stainless steel housing measures 48 ±0.03 mm in diameter and 76 mm in length, and carries an IP65 enclosure rating.

Electrical connection is made through a 3 m 4-conductor, shielded, color-coded PVC cable with strain relief, and the conduit interface is a 1/2-14 NPT conduit fitting with a 7/8 hex.

Configuration Options

The variants of the TQ401 Series are distinguished by measurement range. All three share the same stainless steel construction, surface key mount, electrical characteristics, and accuracy specifications; the difference is the full-scale torque capacity each unit is calibrated to measure.

• Range is encoded in the model number using the pattern TQ401-<RANGE>, spanning from 0-30 ft-lb up to 0-250 ft-lb, corresponding to roughly 0-40 N-m through 0-340 N-m in metric terms.
• Shared performance holds across every range: ±0.2% FSO accuracy, ±0.05% FSO repeatability, 2 mV/V output, and the same overload margins of 150% of capacity safe and 300% of capacity ultimate.

Because overload limits are expressed as a percentage of capacity, higher-range models tolerate proportionally larger absolute torques before reaching their safe and ultimate limits. Metric ranges are also available on request through Engineering.

Key Product Differences

The series comprises three catalog models, each selected by its full-scale torque range:

• TQ401-30 — 0 to 30 ft-lb range reaction torque sensor
• TQ401-100 — 0 to 100 ft-lb range reaction torque sensor
• TQ401-250 — 0 to 250 ft-lb range reaction torque sensor

As ordering examples, TQ401-30 provides a 0-30 ft-lb measurement range, while TQ401-250 covers the top of the family at 0-250 ft-lb. Each model pairs with compatible meters including the DP41-S and DP25B-S.