Customer application 21 September 2017
Valve Control from the Bridge

The restricted amount of space aboard ships presents great challenges for developers of marine equipment. Therefore, compact and versatile automation solutions have gained in appeal. This was also the case for MacGregor Hatlapa GmbH & Co. KG (“MacGregor Hatlapa“), headquartered in Uetersen, Germany. To control the proportional valves in their hydraulic winches, the specialists in deck machinery use an I/O module developed by WAGO specifically for controlling this type of valve.

Maritime hydraulic winches must function in very small spaces and, at times, deliver immense traction forces that should be both quickly and exactly controllable. This task is carried out by proportional valves, which convert a stepless electrical control signal into a proportional, hydraulic output signal. However, in order to easily and precisely set and monitor control variables from a distance, such as traction force and speed, the system needs intelligent electronics and freely-programmable controllers. When searching for a new solution for controlling the proportional valves in their hydraulic winches, MacGregor discovered WAGO.

Deck Handling and Cranes – Here’s How WAGO Supports You:

The low number of components related to use of the 750-632 WAGO I/O Modules leads to cost savings.
The module is compact and powerful.
Its advantage for controlling proportional valves lies in the integration of PLC functionality and proportional valve electronics in one device.

From DIY to New Product Development

The name Hatlapa stands for high-quality deck machinery from MacGregor, a subsidiary of Cargotec, a Finnish specialist in freight handling solutions. For almost a century, compressors, steering gear, and winches bearing the venerable trademark, Hatlapa, have been developed and manufactured in Uetersen. The portfolio includes mooring and anchor winches for merchant shipping, specialized winches for research purposes, and large, offshore winches. The output range of the electric winches extends from a few kilowatts up to 1 megawatt; the latter are used, for example, during anchor handling at oil platforms.

Up until the end of 2013, the proportional valve controller installed in the Hatlapa hydraulic winches was developed in-house. It consisted of an open-source PCB with high-resolution potentiometers, an analog card and, depending on the application, an additional digital card. Using this valve controller, operators could switch the magnetic current on and regulate between a minimum and a maximum value. Henrik Schädel, electrical engineer at MacGregor Hatlapa in Uetersen, did not consider this a satisfactory solution. “Previously, it took three people using radio sets to operate one winch: one turned the potentiometers on the bridge; another watched what was happening within the machine housing on deck; and the third was in the engine room, adjusting the setting on the control cards in the control cabinet. For our largest project to date, there were a total of 101 steps between the engine room and the bridge. In cases like this, setting the parameters for the winches required several long stretches.

MacGregor Hatlapa and WAGO enjoy a long-term business relationship, which extends from connection technology increasingly into automation. The high point so far is the collaboration on the module developed for proportional valves for the WAGO 750 I/O SYSTEM.

Controlling Proportional Valves Easily and Precisely

In the meantime, WAGO's proportional valve module has now become standard for all Hatlapa hydraulic winches. This also includes the large, heavy towing winches, weighing up to 500 t, in which up to 20 proportional valves can be installed, depending on winch size. Here, controllers are needed for hoisting and tacking procedures, pressure limits, controlled braking, and the spooling device. Communication is usually based on Modbus®. Symmetrical on and off switches, so-called bang-bang controllers, are also integrated in the winches and are connected using two digital 2 amp outputs on the proportional valve module.

Reduce Components – Save Costs

With an installation width of only 12 mm, the 750-632 Proportional Valve Module represents a compact and powerful solution for MacGregor, and easily connects the hydraulic valves from the winches into the finely modular, fieldbus-independent WAGO 750 I/O-SYSTEM. Two single-coil valves or one dual-coil valve can be controlled either unidirectionally or bidirectionally. For each channel or coil, the output current is 2 A in 1-channel operation and 1.6 A in 2-channel operation. Both small and larger valves can be controlled reliably, project-specifically, and with high repeatability – even in connection with a lower setpoint/actual value deviation. Operators can parameterize characteristic curves according to the specific application. In addition, WAGO’s proportional valve module features two current-controlled PWM outputs (24 V) with adjustable dither. Winch operators can easily perform start-up and all valve parameter adjustments using WAGO-I/O-CHECK software, or also directly at the controller. The proportional valve module is approved for maritime use by GL and also has UL 508 and IEC ex certifications.

“We can install the proportional valve controller much faster now, since we only have two wires going to the controller. Setting the magnetic current at the winch is also much easier. Actually, I can now do everything by myself from the bridge. In comparison with our proprietary solution, the number of components has been reduced, which also leads to cost savings,” adds Schädel.

Space-Savings due to Power Integration

For MacGregor, the primary advantage of WAGO's new I/O module is the integration of PLC functionality and proportional valve electronics into one device. In comparison with the previous solution, the new module saves valuable space in the hydraulic winch due to its compact design; the reduced number of components means that some, like the 0–20 mA interface, are no longer needed. The lower cabling expense simplifies installation, and the direct access via the control system facilitates parameterization. The control concept can be adapted to the most varied of winches due to the separation of the technology and application levels in the controller logic. This also means that equipment can be replaced without a lot of parameterization labor. A WAGO IPC administers the visualization of the user interface. Using a touchscreen on the bridge, operators can gather information about the system’s status and carry out changes as necessary.

In addition, MacGregor gains a lot of flexibility: previously, the winch manufacturer still used one magnetic current regulator per single coil, even for two-channel controllers. Now, the marine equipment supplier from Uetersen can run both channels in parallel, and in this way operate two single coils or one double coil using only one module.

When asked about the challenges involved in developing the new proportional valve module, Helmut Börjes, Product Manager at WAGO explains, ”We had to accommodate the higher power loss and also the desired variety of functions into a compact design. We succeeded. As a result, different valve types can be addressed problem-free by a single module – and we included the EMC aspects that are so important for marine operations. This benefits MacGregor, and also all of our other customers.”