The Yamato LT-400A is a compact overhead (top-drive) laboratory stirrer main body configured for high-viscosity work at low speed — 10–300 rpm with a rated torque of 0.9 N·m (9.0 kgf·cm), the highest-torque / lowest-speed build in the LT-400 series. A maintenance-free DC brushless motor and a highly sensitive feedback control hold the set speed even as viscosity changes during a stir. Sold as the main body; the LT-400AA adds the stand, rod, shaft and propeller as a complete set.
Key Specifications
| SKU | LT-400A |
| Type | Overhead (top-drive) laboratory stirrer — main body only |
| Application | High-viscosity samples |
| Speed range | 10–300 rpm |
| Rated torque | 0.9 N·m (9.0 kgf·cm) |
| Motor | DC brushless, B-type insulation, 30 W output |
| Rotation control | Feedback control |
| Panel | 4-digit digital speed, overload indication, torque indicator (20% per scale) |
| Chuck | SUS drill chuck for ø8 mm shaft |
| Safety | Current-limiting circuit, thermal protector (motor coil 110 °C), safety cover |
| Power source | Single phase 100–120V ±10%, 50/60 Hz, 200VA |
| Power cord | 3-pin plug, 2 m |
| External dimensions | W146 x D154 x H165 mm |
| Weight | 2.4 kg |
| Included | Clamp holder, safety cover, chuck handle, operating manual, warranty card |
| Complete set SKU | LT-400AA (adds stand + rod + shaft + 60 mm propeller) |
| List price | $1,225.00 |
Application Profile
- High-viscosity mixing — thick solutions, pastes and slurries where torque, not top speed, governs the stir. The LT-400A is the high-torque anchor of the LT-400 range.
- Small-to-mid vessel overhead stirring — top-driven mixing for vessels a magnetic stir bar cannot serve.
- Quiet-bench operation — noise-prevention design suits shared and instrument-sensitive labs.
- Routine synthesis and prep — a light, economical overhead unit for everyday stirring.
Overhead vs magnetic — pick the LT-400A when the sample is too viscous for a magnetic stir bar to couple and the priority is torque at low speed. For higher speed at lower torque within the LT-400 range, see the LT-400B (15–600 rpm) and LT-400C (25–1200 rpm).
Design Architecture
A 35 W DC brushless motor (B-type insulation) drives a ø8 mm SUS drill chuck through a feedback control loop that keeps the set speed steady as viscosity changes mid-stir — the manual highlights this feedback system as the core feature. Speed and load are shown on a 4-digit digital readout with an overload indication and a torque indicator graduated in 20% steps.
Protection is layered: a current-limiting circuit throttles current when applied load exceeds maximum torque, and a thermal protector cuts motor current if the coil reaches 110 °C (recovery after ~30 min cooldown). A safety cover guards the rotating chuck. The brushless motor has no brushes to spark or replace. Housed in a 2.4 kg aluminum die-cast body (W146 x D154 x H165 mm) on 100–120V, 200VA.
Frequently Asked Questions
What speed and torque does the LT-400A deliver? The LT-400A runs 10–300 rpm with a rated torque of 0.9 N·m (9.0 kgf·cm) — the highest-torque, lowest-speed build in the LT-400 series, aimed at high-viscosity work.
Does the LT-400A come ready to stir out of the box? No. It is sold as the main body only. A stand, rod, stirring shaft, and propeller are required to operate — order the LT-400AA set to include them, or add the accessories individually.
Is the LT-400A available in a 220V version? No. Supply is single-phase 100–120V (±10%, 50/60 Hz, 200VA) only; there is no 220V variant of this model in the source.
What is included with the LT-400A? The box contains the LT-400A main body, clamp holder, safety cover, chuck handle, operating manual, and warranty card.
How does the LT-400A hold speed as viscosity changes? A maintenance-free DC brushless motor with a feedback control loop keeps the set speed steady as viscosity changes mid-stir, with speed and load shown on a 4-digit digital readout with overload and torque indicators.
Ordering & Configuration
In the box: LT-400A main body, clamp holder, safety cover, chuck handle, operating manual and warranty card. A stand, rod, stirring shaft and propeller are required to operate and are sold separately — order the LT-400AA set to include them, or add the accessories individually (Y-shaped rack 231086; ø8 x 500 mm shaft 231384; 60 mm 4-blade propeller 231076; other propeller sizes available).
At $1,225.00 the LT-400A is a direct add-to-cart benchtop unit. Note it is a main body only — confirm you have (or are ordering) a stand, rod, shaft and propeller. Supply is 100–120V only; there is no 220V variant of this model in the source.
Warranty: one year from purchase per Yamato terms (repair-parts holding period 7 years after end of production).
LT-400 series: LT-400A (10–300 rpm, high torque, this product) · LT-400B (15–600 rpm) · LT-400C (25–1200 rpm). Complete sets: LT-400AA / -BA / -CA.
