Extrusion machines

NRG digital solid state relay enables OEMs to exchange real-time process data with machine's PLC in real-time. The core functionality of the NRG solid state relays (SSRs), solid state contactors (SSCs) and proportional controllers (SCRs) remains the fast switching of heating elements. On top of this, the NRG can provide data such as current, voltage, kWh as well as relay status to the NRG controller which, in turn, exchanges data with the PLC via different communication protocols such as EtherNET/IP, Profinet, ModbusTCP and EtherCAT. Control of the individual relays also goes through communication protocols thereby reducing wiring time by more than 40%. The integrated current monitoring also allows OEMs to remove external current transformers that are typically used for heater monitoring.

Extrusion machines typically have a mix of 1-phase and 3-phase heating elements. The RGC solid state contactors come in a sleek and compact design to minimize space occupancy in the electrical panel. In the 3-phase variants, the RGC3A switches all the three phases for a more balanced current on all the phases of the heating element whilst, the RGC2A switches two of the heater legs resulting in a more cost-effective and lower heat dissipation. The RGC series comes with an integrated heatsink for a pure plug and play installation. The RGC also carries inductive (motor) load ratings making it suitable to switch motor loads when required.

Proportional controllers, also known as SCRs, take away the burden of converting analog signals from thermocouples into digital (PWM) signals. An analog current (0 - 20 mA, 4 - 20 mA) or an analog voltage (0 - 10 VDC) can be fed directly to the control input of the RGC1P, RGC2P or RGC3P and the output voltage to the heater will vary proportionally. This control method results in a very fine control strategy that minimizes temperature overshoots. Another feature within the RGC.P family of products is the soft start function. Soft start is ideal for applications using short-wave infrared heaters (SWIR) as it reduces the initial inrush current by 40% that occurs when SWIR heaters are switched on from a cold state.

Heater breakdown and thermal runaway due to a shorted heater, are two critical issues in most plastic processes. A failure of the heater will cause a drop in temperature in the heating zone, thereby increasing friction on the screw, resulting in overheating and barrel wear. If a heater shorts out, the temperature in that specific area cannot be controlled and can cause the plastic to overheat resulting in significant material scrap. The RGC1S solid state relay and contactor series integrates current monitoring to detect total and partial heater failures. Based on a "teach" function, the RGC1S compares the measured current to the one stored during the "teach" function and checks for current deviations for up to 6 heaters connected to the relay.

Designed to provide an accurate detection, unaffected by electrostatic discharge and dust build-up, the CA18 and CA30 CAN/CAF sensors are ideal for the monitoring and processing of plastic granules in for instance a hopper or in drying machines where the temperature often rises to high levels. The sensors are designed to tolerate temperatures up to 120°C (248°F). With the TripleshieldTM technology, Carlo Gavazzi capacitive sensors are immune to external interference resulting in a very reliable detection even in harsh environments. Through IO-Link, the CA18..IO and CA30..IO capacitive sensors functionalities can be easily configured for any application requirements.

Many OEMs still rely on current transformers to monitor the heaters to detect heater break downs and/or shorted heaters in plastic processes. The A82 series of current transformers is ideal for this purpose. The input models vary from 0 - 25 AAC up to 0 - 500 AAC. The output can be either analog current (0 - 20 mA, 4 - 20 mA) or voltage (0 - 10 VDC) for easier integration into any existing design.

Switch mode power supplies are a crucial part in powering up most of the critical components within the electrical panel of any plastics processing machinery.
Our SPDC series of DIN-rail mount power supplies offer a number of unique features such as ultra-slim design, integrated PFC and efficiencies up to 96%.
Switch mode power supplies can work on a wide range of input voltage maintaining a very stable DC voltage output to make sure that all the critical components such as PLCs and HMIs are safely powered up.