In which situations does the HCT400's 15 kgf versus the HCT402's approximately 20 kgf make a difference?
The roughly 5 kgf margin between them becomes decisive on valves with stiff centering springs, on short levers, in detented positions, and on old mechanisms with worn joints. If the measured peak force approaches the HCT400's 15 kgf capacity, there is no margin left; in that case the HCT402's approximately 20 kgf capacity is the safer choice. Send us your measurement result for a definitive limit.
The force difference is not a number on its own but a question of safety margin. Working right at the limit of motor capacity leads to: motion slowing down at the end points, the command being applied incompletely in cold weather, and the motor heating up by continuously drawing high current.
Typical situations where the 5 kgf difference is decisive:
- Stiff spring valves: On heavy duty valve banks the centering springs are noticeably stiff.
- Short lever: As the lever gets shorter, the hand force needed for the same spool force increases.
- Detented position: The peak force at the moment of overcoming the detent is well above the normal operating force.
- Aged mechanism: Worn bushings and joints permanently raise friction.
Force is not the only difference between the two models. The HCT402 also works directly on 24V systems, has reverse polarity protection, offers Soft/Dynamic mode selection, and has 3-stage calibration plus an LED + buzzer warning system. The HCT400, on the other hand, is a single-mode, simpler solution for light-to-medium field use.
The selection rule is simple: measure the force first, then choose the model that leaves clear margin above the measured value.
Full coverage of this topic: What Does the HCT402 Achieve, How, and How Much? A Technical Review