A Real Technical Support Case That Prevented Delays During Mold Testing
Injection molds equipped with hydraulic cylinders frequently use limit switches to confirm the position of moving cores, slides and hydraulic actuators.
Although the mechanical installation of the cylinders is often completed without difficulty, electrical wiring can become a critical issue during mold commissioning.
In many situations the mold is mechanically ready for testing, but production cannot begin because the electrical signals from the hydraulic cylinders have not been connected correctly to the injection molding machine.
This real technical support case demonstrates how a simple wiring question, answered quickly with a clear electrical diagram, allowed the customer to complete the mold installation without unnecessary delays.
The case also highlights an important engineering principle: simple electrical solutions are often the most reliable.
The Customer’s Urgent Request
A Vega distributor contacted the Technical Department on behalf of a mold manufacturer that had purchased several V450CM hydraulic cylinders equipped with four-wire limit switches.
The customer needed to complete the electrical wiring immediately because the mold trial was scheduled for the end of the same day.
The question was straightforward:
How should the limit switches be connected in series?
The cylinders were equipped with microswitches having four wires:
- Black
- Brown
- Blue
- White
Without the correct wiring information, the customer could not complete the mold installation or begin testing.
Why Electrical Wiring Is So Important
Modern injection molds contain numerous hydraulic movements.
Typical applications include:
- side cores;
- locking cylinders;
- unscrewing mechanisms;
- ejector systems;
- hydraulic slides.
Each movement normally requires electrical confirmation before the molding machine can continue with the next production step.
If even one limit switch is connected incorrectly, the PLC may never receive the expected signal.
The consequences can include:
- interrupted automatic cycles;
- machine alarms;
- incorrect sequence control;
- commissioning delays;
- unnecessary troubleshooting.
For this reason, correct electrical wiring is just as important as proper hydraulic installation.
Vega’s Technical Solution
Instead of providing only written instructions, the Vega Technical Department prepared a simple wiring diagram specifically for the customer’s application.
The response included one very important recommendation:
Only the wires shown in the drawing should be connected. All remaining wires must be left disconnected.
This apparently simple instruction eliminates one of the most common causes of commissioning problems: connecting unnecessary wires that may interfere with the electrical circuit.
The Series Connection Diagram
The supplied drawing shows six MS5 limit switches connected in series.
The switches are installed on six hydraulic cylinders positioned within the mold.
The series wiring is connected directly to the machine terminal box.
Only two conductors from each switch are used:
- Blue
- Black
The remaining wires are intentionally left unused.
This simplified configuration provides a clean electrical installation while reducing wiring complexity and minimizing the possibility of connection errors.
Why Leave the Other Wires Disconnected?
Many technicians assume that every wire coming from a sensor must be connected.
In reality, this is not always true.
Modern limit switches are often designed to support different wiring configurations depending on:
- machine control systems;
- sensor technology;
- voltage supply;
- output configuration.
Using unnecessary conductors may create unwanted electrical paths or generate incorrect signals.
For this reason, the Vega Technical Department clearly instructed the customer to connect only the conductors shown in the wiring diagram and to leave every other wire isolated.
Advantages of Series Wiring
Connecting multiple hydraulic cylinder limit switches in series offers several practical advantages.
Among the most important are:
- reduced wiring inside the mold;
- fewer cables entering the electrical cabinet;
- simplified installation;
- faster troubleshooting;
- lower risk of wiring mistakes;
- improved maintenance accessibility.
For molds containing several hydraulic movements, reducing wiring complexity can significantly decrease installation time.
Avoiding Commissioning Delays
One interesting aspect of this case is that no hydraulic problem existed.
The cylinders had already been manufactured and installed correctly.
The only obstacle preventing mold testing was uncertainty regarding the electrical wiring.
Without a clear connection diagram, technicians might have spent several hours identifying the correct conductors or attempting different wiring configurations.
Instead, the Vega Technical Department supplied an immediate solution using a simple and unambiguous electrical drawing.
This allowed the customer to complete the installation quickly and prepare the mold for testing within the required schedule.
The Importance of Clear Technical Documentation
This case demonstrates that technical support is not limited to solving mechanical failures.
Many production delays originate from installation questions rather than defective components.
Providing accurate technical documentation at the right moment can often save far more time than replacing parts.
In this case, a single-page wiring diagram eliminated uncertainty and provided the customer with immediate confidence during mold commissioning.
Lessons Learned
Several important engineering lessons can be drawn from this real support case.
First, electrical wiring should always follow the manufacturer’s instructions rather than assumptions made during installation.
Second, connecting additional wires simply because they are available may create unnecessary complications.
Finally, a clear and easy-to-read wiring diagram is often the fastest way to solve installation problems.
Good technical support is not measured only by solving complex engineering challenges.
Sometimes the greatest value comes from providing simple, practical solutions exactly when the customer needs them.
Engineering Conclusions
This real technical support case demonstrates that successful mold commissioning depends on much more than correctly selecting hydraulic cylinders.
Electrical integration is equally important.
When a customer urgently needed to connect several hydraulic cylinder limit switches before mold testing, the Vega Technical Department responded with a straightforward wiring diagram and one essential instruction: connect only the specified wires and leave all others disconnected.
The result was a clean, reliable electrical installation that enabled rapid commissioning without unnecessary troubleshooting.
For mold builders, maintenance technicians and automation engineers, this case illustrates an important principle:
The simplest wiring solution is often the most reliable one, provided it follows the manufacturer’s specifications.
