Wiring Electrical Systems – Eliminate Maintenance and Save Time

Drilling holes precisely and at high speed – this is the essential requirement the CNC drilling machines from Schmoll Maschinen GmbH have to meet.

The machines produced by this mid-sized company are used globally in electronics manufacturing. Numerous electronic devices, from smartphones to flat screen TVs, contain PCBs that were manufactured using this equipment. When wiring the electrical systems, Schmoll relies on TOPJOB^® S Rail-Mount Terminal Blocks with push-in spring pressure connection technology from WAGO.

The constant drive for miniaturization in electronics has also increased the demands placed on the machines. They have to drill both quickly and with high precision. In addition, they have to compensate for any unevenness present in the PCBs. “The spindles rotate at up to 300,000 rpms,” says Winterschladen, “and drill not only quickly, but extremely precisely as well.” The smallest holes that can be made using the machines have a diameter of a mere 30 µm, with a precision better than 2 µm.

Until around three years ago, Schmoll used standard rail-mount terminal blocks with screw-clamp connections for its machines. “Since we are always looking for improvements in design and simplification in our manufacturing, we tested the TOPJOB® S Rail-Mount Terminal Blocks from WAGO for our electrical systems,” says Winterschladen. One of essential advantages of the TOPJOB® S Rail-Mount Terminal Blocks is the spring pressure connection technology, which does not require screws. An optimal connection is thus always guaranteed. “Screw connection technology always depends on how firmly the screws are tightened,” recalls Thom. Accidental loosening of screws due to vibration, which can occur during transport, is now prevented due to the use of the new maintenance-free TOPJOB® S Rail-Mount Terminal Blocks. “Previously, errors caused in part by poorly tightened screws had to be remedied by our service employees during commissioning at the customer’s facility,” says Winterschladen, citing a disadvantage of the old screw connection technology.

When changing the processes in the manufacturing line, it is always important that the employees affected by the change also participate in the decision. “Therefore, we brought everyone on board during the first tests using the TOPJOB® S Rail-Mount Terminal Blocks,” says Thom, explaining the conversion strategy. Even if there was some initial skepticism, it very quickly turned to overwhelmingly positive feedback from the employees. The wiring can now be accomplished faster thanks to the spring pressure connection technology. Above all, the quality of the connection no longer depends on how firmly the worker tightened the screws.

Through terminal blocks, as well as double-deck and triple-deck terminal blocks, are used for wiring various cable cross-sections in the electronic components of the CNC drilling machines. In addition, so-called component connectors are also used. These allow passive components such as resistors and diodes, as well as small circuitry, to be inserted directly into suitable carrier terminal blocks. Signal adaptation can thus be realized easily without additional components. The multilevel terminal blocks save a great deal of spaces and make the electrical assembly very compact. All rail-mount terminal blocks can be provided with continuous marking strips, which are printed using a thermal transfer printer from WAGO. Uniform marking ensures clear organization, which makes the wiring that much safer. “In contrast to the multilevel terminal blocks that we previously used, there are now marking strips for all levels, which really contributes to efficiency,” states Thom. “It took a bit of getting used to, but we are really satisfied with the new solution.”

“We require exceptional quality in the machines produced in our manufacturing facilities,” emphasizes Winterschladen. After assembly and set up, each machine undergoes an internal service approval. Finally, the machine must complete an overnight functional test, in which the tool changing function is extensively tested. “This simulates an operational period of around three months,” explains Winterschladen. After delivery, Schmoll service workers commission the machine at the customer’s facility. Speed is also of essence here, so production can begin as soon as possible. “The new TOPJOB^® S Terminal Blocks in the electrical systems of our machines provide benefits specifically for commissioning,” says Markus Winterschladen with confidence. Screw connections, which would loosen during transport, are now a thing of the past.

Author: Tarak Viol, WAGO GmbH & Co. KG