Small Drives Play A Big Role In Energy Efficiency

Employing Variable Speed Drives and high efficiency motors to ensure energy efficiency on a new large-scale capital project isn't difficult in principle. The high number of smaller motors being used on any one site can often mean that the savings are comparable to that of applying a drive to one large fan motor for example, but the capital investment can be far lower. The contribution to overall equipment efficiency (OEE) is also therefore higher. "The idea that small drives can make a large contribution to energy saving is born out by the figures", comments Justin Peters, Technical Manager at AC Tech Lenze and who has played a central role in developing a new simple-to-use Energy Saving Programme for customers. "The recent increases in energy costs have contributed to the faster payoff times for small drives, the overall potential saving is huge and we believe it is currently being overlooked", continues Peters. There are often just one or two very large motors on a production or processing site, whereas the majority of sites with any level of basic factory process or automation will include many smaller electric motors.

Just a few production lines can include hundreds of small motors and it is in these situations where the cumulative savings could be huge; almost two-thirds of industrial electricity consumption is due to the running of electric motors and drive systems. The other attractive reasons for focusing on small drives for energy saving are the speed at which they can be installed and their simplicity of use. The latest generation of low-cost Lenze AC Drives for example are ready-to-run straight from the box with useful factory settings already in the memory chip for fan and pump applications and simple controls on the front of the drive for speed adjustment and basic programming. The footprint of a "submicro" drive is also so small now that it can often be fitted directly into the existing control panel on a machine and wired in with a minimum off fuss (the footprint of a 0.25kW Lenze SMD Drive for example is just 93mm wide by 83mm deep). This ease of use means that the SMD Drive can be installed and working in a matter of minutes. The result is that by focusing on small drives for energy saving the activity does not have to be a capital or labour intensive one, and can be implemented very quickly. For a modest investment, many smaller motors from 0.25 to 22kW could be included in an energy efficiency improvement programme and provide cumulative savings that could reduce energy costs by thousands of dollars.

Industrial I/O Pad Goes Wireless

ABB Low Voltage Controls has introduced a wireless I/O pad, simplifying the process of transmitting and receiving data via a central control system for complex automated applications in factories. The Wireless Input/Output Pad (WIOP) forms part of ABB's range of tools used to create a factory environment where automated machines can be operated wirelessly. The pad has a total of eight inputs and eight configurable input/outputs, which are connected to conventional wired sensors and actuators using short cables, greatly reducing the amount of communicating wires required for factory machinery. Communication is performed between the machine's control system and the I/O pad via WISA-com; ABB's software interface that manages all wireless communications. The control system is connected to the input/output module WDIO100 via a fieldbus.

Two duplex antennas connected to the I/O module receive all radio communications to and from the sensor/actuator distributors, as well as from all wireless Proximity Switches within the machine. This way, only a 24V DC supply is required to each WIOP100 wireless pad. The WIOP100 pad reduces installation time used to make tool changes or for upgrading, as signal connections do not need to be cut. Following any tool changes to machinery, the I/O pad becomes operational as soon as the supply voltage is re-established. By using a 2.4GHz bandwidth, the WIOP100 reduces service interruptions. It is unaffected by typical sources of interference within an industrial environment, such as other Wi-Fi services or radio frequencies. The WIOP100 is highly versatile, it can be used in many different processes and applications such as monitoring and controlling turntables for robotics and handling applications, in production lines with decentralised sensors and actuators, and for assembly machines where frequent tool changes are required, amongst other uses. The WIOP100 is used as part of ABB's WISA family of wireless products. WISA, or Wireless Interface to Sensors and Actuators, has been developed by ABB to enable real-time factory automation at the field device level and is based on standard low cost hardware.

PLCs Upgrade Processing Power

New from Idec Izumi, the Pentra PLC range includes 12 CPU modules that are compatible with the company's current MicroSmart input/output modules and are the same physical size as the present CPUs. More than double the memory size, up to 275 times faster processing speed and the capability for floating point maths means the Idec Pentra PLC can handle most complex tasks that are thrown at it. The CPU has high speed counter inputs counting at a maximum frequency of 100kHz with 32bit word comparisons and PID with an advanced auto tune feature are other improved functions. Master and slave expansion modules have been introduced enabling up to a maximum of 512 I/Os to be connected via an expansion cable if necessary.

This means the Idec Pentra PLC can be accommodated in narrow width cabinets as the master/slave units can be situated anywhere in the I/O range. Network capability has not been ignored either: Ethernet connectivity is possible via the new web server, up to two AS-I network modules can be addressed and the Idec Izumi Pentra has the ability to operate as a Modbus master or slave. The upgraded programming software, WindLDR V5.0, gives the user the options of online editing and runtime program downloading which means the Pentra does not have to stop its scan while programming modifications are undertaken. If the user wants to develop a program and the PLC is not available for testing, then program simulation can be run directly on the PC.