How to Choose a Mould Protection Vision Camera System for Your Injection Moulding Machine

Author : Paheej Machinery | Published On : 29 Oct 2026

<p>A high-resolution camera does not automatically protect your mould. If the camera inspects at the wrong moment, or its result never reaches the machine's mould-close circuit, a defect can be detected and the mould can still be damaged. That is why signal compatibility matters as much as image quality when you select a <strong>mould protection vision camera system</strong>.</p>

<h2>Why Signal Compatibility Matters</h2>
<p>The camera and the injection moulding machine must exchange the right signals at the right time in every cycle. The machine tells the camera when the mould is open and ready to be checked. The camera then tells the machine whether it is safe to close. If either side is missing or mistimed, the system cannot protect the mould.</p>

<h2>Signals the Machine Should Provide</h2>
<p>For inspection after ejection, two signals are normally needed:</p>
<ul>
<li><strong>Mould open complete:</strong> confirms the moving platen has reached its full open position.</li>
<li><strong>Ejector back:</strong> confirms the ejector stroke has finished.</li>
</ul>
<p>If the camera starts before the ejectors retract, it may see moving pins and raise false alarms. Operators then lose trust in the system and often bypass it. Some setups also use a mould-close start signal, so the inspection result is ready before closing begins.</p>

<h2>The Mould-Close Permit Output</h2>
<p>The most important output is the mould-close permit. It should connect to a machine input that genuinely blocks mould closing. An alarm lamp or buzzer only warns the operator, and the mould can still close. The permit should also be fail-safe, so that a power loss, broken cable or controller restart stops the machine from closing. Ask suppliers to demonstrate this behaviour, and have it validated by a qualified engineer.</p>

<h2>Robot Interfaces: EUROMAP 67, EUROMAP 12 and SPI</h2>
<p>Many machines already expose cycle signals through a standard robot interface, and a mould protection system can often use the same port. EUROMAP 67 is common on newer machines, EUROMAP 12 appears on some older ones, and SPI-based interfaces are used on others. Remember that a matching interface name does not guarantee compatibility. Always confirm the actual pinout and configuration of your machine.</p>

<h2>Electrical Points to Check</h2>
<ul>
<li><strong>Signal voltage:</strong> many modern machines use 24 V DC, while some older ones use 110 V or 230 V AC relay circuits that need interface relays.</li>
<li><strong>PNP or NPN:</strong> the camera inputs must match the machine outputs, or accept both types.</li>
<li><strong>Output type:</strong> a dry relay contact is flexible, while a powered transistor output must match the machine's input type.</li>
<li><strong>Galvanic isolation:</strong> protects the camera controller from electrical noise and ground loops.</li>
</ul>

<h2>Different Machines, Different Needs</h2>
<p>All-electric machines run fast cycles, so the gap between ejector-back and mould-close may be very short. Vertical and rotary-table machines need table-position signals and a camera for each station or a suitable mount. Multi-component and 2K machines may need extra signals and several inspection points in one cycle.</p>

<h2>What a Good System Should Inspect</h2>
<p>Depending on the mould, a capable system can check for missing or unfilled cavities, parts that are not fully ejected, slide-core movement problems, ejector pin retraction issues, insert misplacement, flash and short shots. Each check needs a trigger at the correct stage of the cycle.</p>

<h2>Quick Pre-Purchase Checklist</h2>
<ul>
<li>Record the machine make, model, controller and interface type.</li>
<li>Confirm signal voltage and PNP/NPN type.</li>
<li>Check that mould open complete and ejector back signals are available.</li>
<li>Identify the machine input that blocks mould closing.</li>
<li>Compare the time between ejector back and mould close with the system's response time.</li>
<li>Ask the supplier to demonstrate permit behaviour on power loss.</li>
</ul>

<h2>Final Thoughts</h2>
<p>Choosing a mould protection system is an electrical decision as much as an optical one. Start with your machines, not the brochure, and hold every supplier to the same checklist. To see how a vision-based solution can be integrated with compatible machines, explore the <a href="https://paheej.com/mould-protector-vision-camera-system/">mould protection vision camera system</a> from Paheej Machinery.</p>