Mold Hot Runners Materials Pages 21 to 38 By Chad Root and Manny Diaz Serious vulnerabilities exist when a mold builder or molder has problems with hot runner cable connections. However, there are solutions and ways to ensure you always use the right cables on the proper circuits. Here are the top ive problems routinely experienced in the ield. 1. Pushed-Back or Bent Pins Imagine two pushed-back pins on the top of a mold in a -pin layout heater connector. Note the -inch-long machined pin with a spring for press-itting into the back of the male insert. These pins are delicate (/-inch-diameter exposed) and can easily be bent or pushed back when being mated to a female con-nector on a mold box, cable or hot runner controller. Bent pins are likely to interfere with a connection and cause open circuits. Pushed-back pins are especially prob-lematic when troubleshooting open circuits or other alarms because they can be intermittently connected. This can be seen on a hot runner controller as an open heater or thermo-couple, and even thermocouple reverse or shorts. One solution to hot runner cable connection issues is 24-pin male and female connectors with a single-latch hood. 4. Loose or Broken Latches Worn levers and latches allow a loose it between cables and the adjoining hot runner controller or mold box. These loose connec-tions cause intermittent currents and sometimes open circuits. 5. Missing or Loose Ground Wire Connections Grounding from the hot half to the mold box through the cables and the controller and then to the facility ground is critically important. Unfortunately, ground connections are often loose, ilthy dirty or missing entirely. Solutions: A Better Connector A quick ix includes -pin male and female connectors, which have a single-latch hood. Unlike the -pin connectors, these are heavy-duty. The pins won’t bend or get pushed back and are rated for amps. They also have screw terminations for inserted wires and are much easier to connect to mating mold boxes, cables or controllers. To ensure heater and thermocouple cables are clearly differ-ent, use dual-latch hoods for one and single-latch for the other, or use a combination heater and thermocouple cables with a single hood. A quick fi x includes 24-pin male and female connec-tors, which have a single-latch hood. 2. Pushed-Back Inserts An example of this is a female insert base in a single latch hood. The metal inserts for each opening are press-it into the base and can often be pushed back when inserting the mating and male connector. Pushed-back pins or inserts are a common problem that can result in an intermittent current or an open circuit. You can easily check to see if they are seated correctly by pressing a multimeter lead into the socket. If the insert is unseated, it will easily slide back and out of the socket. 3. High Amp Deterioration Now, imagine that female insert base but with signs of burning and deterioration around some of the insulated holes. These types of connectors are only rated for amps, yet many shops use them for manifold circuits that can easily exceed amps. It is highly recommended that molders ensure frequent preventative maintenance, increase amp ratings for larger heater applications or upgrade to a more robust connector system. FOR MORE INFORMATION Spark Industries 574-606-4243 / 630-849-1779 / fastheatbyspark.com Chad Root, Managing Partner, Sales and Administration Manny Diaz, Production and Engineering 38 MoldMaking Technology — — JULY 2023 Image courtesy of Fast Heat by Spark Industries. How to Overcome Five Common Hot Runner Cable Connection Problems