Vacuumschmelze, a global manufacturer of advanced magnetic materials and related products based in Hanau, Germany, has company roots that date back to 1914 with the world's first vacuum melting furnace. Today the company operates in more than 40 countries with 4,000 employees, and annual sales of approximately $635 million.
For heat, the company uses fan blower heaters to circulate warm air supplied by the district network of the Hanau municipal utility. The fan blower heaters' controls were installed in 2008 and were due for an update.
Short and Precise: IO-LinkIO-Link represents a new communication standard for sensors and actuators, as defined by the Profibus User Organization. The IO-Link technology is based on a point-to-point connection of sensors and actuators with the control system. Sensors and actuators can transmit cyclic operating data as well as comprehensive parameter and diagnostics data using a simple, unshielded three-wire line.
"Even back then, our compact starters met our rigorous requirements with regard to modern fan control, but we wanted to take advantage of advancements in the technology since then," said Thomas Ost, responsible for building automation and control technology department at VAC. He explains that in updating the VAC Hanau facility's blower heater controls, he sought a compact solution that combined both short-circuit and overload protection as well as a contactor. "Compact starters with IO-Link communications were the ideal solution for us," he says.
Reduces Power Losses by Up to 80%
Compact starters, like Siemens Sirius brand, not only comply with VAC's requirements, but they also deliver many additional benefits such as reduced energy consumption, a wider range of settings, and considerable wiring and service advantages.
For example, compared to conventional feeders, the power loss in some compact starters has been reduced by up to 80%. These savings multiply quickly, especially with VAC having approximately 20 on-site control cabinets in nine production halls. and each of these needing three to four devices.
The Vacuumschmelze company opted for IO-Link-capable Siemens SIRIUS 3RA6 compact starters to update the starting and control of fan blower heaters in its production facility.
Ost said he appreciates options in compact starter models, but each model having the same size plus a wide range of settings to cover loads from 0.1-32 A is a plus. "Naturally, this makes maintenance and keeping parts inventory much easier," he says. Technicians save a lot of time in wiring, too. "A spring-loaded connection system makes connecting devices fast and safe, helping to cut the time and expenses we need to assemble control cabinets and boxes," Ost said.
Central Energy Infeed and Permanent Wiring
In addition, two- and three-slot infeeds are beneficial. These facilitate the side-by-side assembly of compact supply batteries. The central energy infeed as well as the integrated PE terminal are special highlights.
"These features save additional coupling," Ost said. "So not only are space requirements in the control cabinet minimized, but this also helps reduce wiring expenses significantly. That's because only the motor cables have to be directly connected to the infeed system."
The compact starters with infeeds also save lots of time when servicing is needed. Thanks to permanent wiring, technicians can replace devices quickly. They only have to remove the auxiliary switch blocks from the device, so the respective compact starter can be unlocked and pulled towards the front. Then they can adjust the current range of the newly attached device via the rotary switch on the device front. Of course, this also eliminates any confusion over control lines, too.
Thomas Ost demonstrates the hand-held terminal: "The Siemens Sirius 3RA6 compact starters provide a compact motor starter solution that’' further enhanced by its IO-Link network communications."
IO-Link for Communication Down to the Actuator Level
In VAC's 2008 implementation of compact motor starters, all the devices were connected to digital I/O modules of the Siemens Simatic ET200S distributed I/O system. With the 2010 update, the switching was simplified further. That's because both the compact starters and the contactor can now be connected via IO-Link, too. "This improved the motor feeders' installation, commissioning and operation even more," Ost said.
IO-Link simplifies wiring in other ways. For example, with an unshielded three-wire connection, one port can be used to link up to four compact starters — or contactors — with an IO-Link communication interface and an assembled IO-Link module.
Because a master module has four such ports, it can control up to 16 compact motor starters or contactors. With a width of just 15 mm, it can be integrated in the Profibus- and Profinet-capable ET200S.
In short, only the first compact motor starter in a group of four has to be wired to a 24 V supply so it can exchange signals with IO-Link. And pre-fabricated flat cables can be used. This greatly simplifies the wiring compared to the previous parallel wiring that separate devices needed. As a result, the control circuit only needs five connections.
Fast, Easy Parameterization of IO-Link Feeders, With Greater Safety
Simplifying the control circuit makes the planning process much easier. Even the IO-Link feeders' parameterization is easy. With the Port Configuration Tool (PCT) that's included in the Simatic S7 software (v5.4 or higher), the feeders no longer have to be individually addressed via digital outputs and read out via digital inputs as in the past.
Instead, a simple mouse click in the PCT sets the correct configuration, and the master module automatically determines the address range with inputs and outputs. "It's a great time saver to be able to specify the suitable current range for each individual compact starter using a pull-down menu,“ Ost said.
"System safety is enhanced, as well," he adds. For example, if a service technician replaces a compact starter with one that has a current range outside what's been set by the PCT tool, the control circuit immediately detects and rejects it, he says. The same occurs if triggered by the devices' patented end-of-life detection. What's more, if a device's main contacts weld, they are mechanically separated upon disconnection of the control voltage — a condition that's then indicated on the device.
Comprehensive Diagnostics Options Down to the Actuator Level
The comprehensive diagnostics of the compact starters provide VAC with specific advantages, especially with distributed electrical controls VAC uses for operating the fan heater blowers in its Hanau production facility.
For example, if an overload tripping event in the compact starter is detected, it can now be reset via IO-Link. In addition, the devices can differentiate between overload and short-circuit tripping events. They can also detect the switching state, the main contacts' end-of-life status, missing supply voltage, running cooling time and other conditions, all via IO-Link.
Ost added that he finds even more benefits in the system's commissioning as well as its emergency operation without system control. For example, technicians can commission a system using an optional hand-held terminal that simply plugs into an available flat cable port of the last device of an IO-Link group. Similarly, this operator panel can be employed for operating the compact starter even without a PLC. "This supports emergency operation," Ost said. "So, even if the system fails, the facility will still be heated."
With Siemens SIMATIC S7 software version V5.4 or higher, the integrated PCT software tool lets operators easily address and assign parameters to the IO-Link stations.
Siruis 3RA6 Compact Starter With IO-Link
The VAC plant's fan blower heaters are connected to the building control system from via the Simatic S7-300 system control using Profibus. This is possible because IO-Link enables integrated signal technology down to the actuator level. It also eases the solution's integration with a northbound control system.
The combination of the space-saving compact starter with IO-Link's control communications has proven to be VAC's most cost-effective solution for simplifying the planning, commissioning, operation and maintenance of its heater fan blowers. In addition, VAC is saving a lot of energy — in turn, saving costs and the environment — with up to 80% reduction in power losses across all the compact starters.
The diagram shows the space savings supported by the application of the Siemens SIRIUS 3RA6 compact starters in connection with IO-Link.