Motorised Levelling by Powered Steadies


Motorised Winterhoff Steady
Motorised Winterhoff Steady

Winterhoff is a German trailer component manufacturer that first produced this format of corner steady - hence its name.

Because its a good design as well as an easy one to copy many others now make Winterhoff steadies, but they're still called Winterhoff if they look like the original product. Existing Winterhoff steadies are motorised by fitting 12VDC gearmotors in a DIY procedure easily accomplished at home by anyone with moderate tool skills. The motors are wired back to a control unit which communicates Bluetooth to the mobile phone app.

Since the gearmotors required to motorise the corner steadies are very expensive, alternatives are always being sought. One such alternative is the use of inverted and modified electric scissor jacks. Though the motors and gearboxes fitted to these electric jacks are of a lesser quality than found in industrial-grade gearmotors, they are sufficient for the relatively light duty that they can be expected to be put to.

Further information on electric scissor jacks can be found at the bottom of this page.

See the video Motorised Leveller video

 Available Extensions:

Levelation System
Levelation System


Levelling Screen
Levelling Screen

Motorised Levelling with Winterhoff Steadies

The App is also has remote control for a caravan leveller   The screen shows 2 levelling crosshairs which will centre when the caravan surface on which the mobile phone lies is level. Control for four levelling motors is provided on the same screen. The Levelling Controller support four bi-directional12V DC motors with up to 25A of DC current. No limit switches are required as the controller senses end-of-travel and cuts the motor current automatically. The mobile phone is placed flat on a table and you tap the UP/DOWN pushbuttons to drive the corner lift motors until the dots centre on the crosshairs. Levelling motors are supplied with ramped start-up current and are automatically shut down when a current spike indicates that end-of-travel has been reached in either direction. Levelling motor current is displayed on the screen of the mobile phone. The motorising of the corner steadies is an easy DIY project available to anyone with moderate hand skills. See a step by step tutorial and video here.

Calibrating the Levelling Crosshairs

Many mobile phones have camera lenses that stand proud of the rear surface of the device and prevent its lying flat on its back. To eliminate these, or other instrument errors that may exist in the mobile phone or its jacket, you can calibrate the crosshairs to zero by placing the phone on a flat and level surface, and then double tapping the Caravan Pilot title. The phone will buzz and the red dots will centre. This calibration will apply until the app is terminated.

End-of-Travel Detection

The controller does not require limit switches - end-of-travel is detected by the sharp rise in motor current that occurs when the motor is slowed at reaching the limit of its travel. (This can also happen when the motor encounters some other insurmountable obstacle). When the motor current reaches or exceeds 25A while extending the leg the control unit assumes that end-of-travel has been reached or an insurmountable obstacle has been encountered. For retracting the leg the current limit is reduced to 15A since there will normally be less load on the motor during this operation.

Once end-of-travel is detected further movement in that direction is blocked by the control logic. The block is removed when travel in the opposite direction is initiated.

Power Switch

There are 3 current paths through the controller:

  1. The main motor current path flows from the 50A Anderson plug through the 20A circuit breaker, through the enabling relay contacts, and then through the motor armature. Switching OFF the circuit breaker will break the current path and stop any runaway motor. Why a 20A circuit breaker when 25A is allowed? Domestic circuit breakers generally trip at between 150% and 200% of their nominal current rating. A 20A circuit breaker will trip when it passes a current of between 30A and 40A. The circuit breaker is not intended to protect the motors - that is done by the electronic control. The circuit breaker is intended to prevent damage after a component failure.
  2. The second path flows from the 50A Anderson plug through the MB+ Output, through one pole of the external power switch, back in through the 12E terminal, and through the internal relay modules to energise the main motor relays. Switching the power switch OFF will remove the current that energises the main motor relays.
  3. The third path enters the controller through the second pole of the external power switch and into the terminal marked 12V. It powers the MPU and Bluetooth modules. The source of this current can be either common to the 12E source (the main battery) or from a dedicated alternate battery that is not subject to the voltage fluctuation and depletion of the main battery. If such a secondary battery is implemented it will be float-charged from the main battery whenever the power switch is set to OFF 
The Electric Scissor Jack

An electric scissor jack can be used in place of a motorised corner steady. The quality of the motor and gearbox on the jack are often less than found in industrial-grade gearmotors, but the price is also commensurately lower, and the low frequency of operation of levelling motors does not demand such a high level durability. 

Ground Contact
Ground Contact

The existing steady is removed and the electric jack mounted on a steel 'T' made of flat bar, with holes drilled to coincide with those used to attach the steady to the frame, Extending the jack takes a minute or less, depending on the distance to be covered, and the jack is powerful enough to lift the caravan should a wheel need to be changed.

Some modifications to the jack are required. The crown at the topmost point must be removed as it only increases the jack's profile without being useful. A skid must be welded onto the rear lower scissors member to protect the motor from contact with the road. And the footprint area must be increased to spread the load on soft surfaces.

The jack is fitted with microswitches to signal travel limits, but these are not used due to their inherent lack of reliability. A motor current in excess of 5A is taken as the retracted limit having been reached. The jack's leadscrew is fitted with an axial-load thrust bearing which makes the jack able to endure larger forces when extending. Therefore the current limit for extension is set to 8 Amperes.

Scissor Jack Quick-release Mounting
The Quick-release Mounting
The Quick-release Mounting

In order to make the electric scissor jack available for other purposes, such as jacking up a car, it can be mounted in a quick-release bracket, which requires only one 17mm AF nut to be loosened to release the jack. When provided with an extension power cable the jack can hen be used for other purposes.

Mixing Motor Types

Since the  motor current limits vary between a worm-drive gearmotor and a motorised scissor jack individual motor types can be coded into the firmware to match the actual configuration. This allows the mixing of motor types amongst the four corners of the vehicle.