Can I control more than one hydraulic lever on the same vehicle with a single system?
Each manual lever needs a servo motor of its own; the motors are mounted separately, their supplies planned separately and they are calibrated one by one.
No — a servo motor moves only the single lever it grips. If you want to control two hydraulic functions you need two motors, and for three functions three motors. The motors are mounted separately, their supplies are planned separately and they are calibrated one by one; the only thing shared is the remote control in the operator's hand.
Why two levers cannot be driven with one motor
The mechanical reality is clear: the motor grips the lever with a bracket and pushes it about its own axis. This connection is physical; the plane the lever moves in, its stroke range and its end points are specific to that lever. Driving two levers with one motor would require putting a mechanical selector between them, and that would remove the ability to work the levers independently and at the same time. What is expected in the field is exactly the opposite: the operator wants to be able to slew at the same moment as raising the boom.
For the same reason, carrying a single motor between levers by hand is not a solution either. The calibration is specific to the lever; every time the motor is taken off, the bracket position, the working range and the direction definition have to be taught again. A movement that would take two minutes turns into a recalibration job every time.
What has to be planned in a multi-lever installation
- Layout: The distance between the levers on the valve bank must be enough for the motor bodies and their brackets to fit side by side. The HCT400 motor body measures 165 × 90 × 40 mm; the clamping and mounting arrangement is worked out separately for each motor.
- Supply: The supply and the fuse for each motor must be planned separately, and the total current must be assessed against the capacity of the battery and the main cable; fuse selection and mounting is done per line.
- Calibration: The working range and the direction definition of each motor are done separately; the mechanical end points of the levers differ from each other.
- Control logic: Which joystick axis will drive which lever must be settled at the installation stage.
What the compatibility assessment looks at
Because the installation grows more complex, on multi-lever projects a compatibility assessment with photographs of the valve bank and the levers before mounting is recommended. The inputs to the assessment are these:
| Input | What it determines |
|---|---|
| Number of levers | How many motors and how many control axes are needed |
| Distance between the levers | Whether the bodies and the brackets fit side by side |
| Measured peak force of each lever | Whether the kit force is enough — measurement method |
| Supply voltage | Whether it is 12V or 24V; the HCT402 works in the 7–40V range |
| End points of the levers | The calibration range of each motor |
Where this installation becomes difficult
A multi-lever installation is not applicable on every vehicle. In the following cases the project is reconsidered before installation begins:
- If the levers are very close together the brackets and the bodies may not fit side by side; this is a mechanical limit and is not overcome by the choice of product.
- If some of the levers are detented and others spring-returned, the movement logic has to be defined separately for each lever; a single control scheme does not suit them all.
- If the valve bank is inside a narrow cab, the movement space of the motors and the cable routing reach a dead end.
- If one of the levers is markedly heavier, the whole installation has to be sized to the force requirement of that lever.
- If the supply line and the battery cannot take the motors running at the same time, the problem comes out before the installation is finished.
The work to be done, in order, is this: count the levers, measure the distance between them, measure the peak force of each lever with a spring scale and photograph the valve bank. With these four pieces of data you can see whether the installation is feasible before mounting begins. Phasing the installation is an option too: starting with the most used lever and adding the others after you have seen how the system works in the field prevents both layout mistakes and buying motors you do not need.
The full topic: What is a hydraulic lever retrofit kit?