Simplify Machine safety monitoring eliminating redundant relay logic
The stand-alone G9SP Safety Controller from Omron STI is a game
changer eliminating expensive relays and redundant logic controllers
taking significant cost out of your machines. The G9SP Safety
Controller offers simple, easy-to-understand programming for even
the most complex safety control circuits, and can be programmed
from a PC via USB connections, or from a removable memory card.
Plus the Intuitive Configurator software makes programming and de-
bugging a breeze.
These software-based stand-alone controllers are quickly programmed to satisfy the complex safety control needs of small and mid-sized machines, and are easily reconfigured to solve evolving machine set-up needs. Three base models with a range of I/O options are available to satisfy varied application requirements, and four types of expansion I/O units are available for hard-wired diagnosis or standard signals. List prices start at under $600, making the G9SP the most cost effective programmable safety controller available today.
G9SP programmable safety controllers are an ideal stand-alone safety control solution for machinery used in packaging, food and beverage, automotive component, injection molding, and printing applications where customer-driven machine set-up changes demand equally flexible safety solutions. These controllers can also seamlessly connect to an Omron PLC and communicate using the FINS protocol for a complete Omron control solution platform.
G9SP programmable safety controllers deliver clear diagnostics and monitoring via Ethernet or Serial connection, and support direct connection with non-contact switches and safety mats. They are DIN track-mountable or can be mounted with M4 screws, require a 24 VDC power supply, and can operate in temperatures ranging from 0 to 55°C. They are ISO 13849-1(PLe) and IEC61508(SIL3) certified. “In addition to being a price leader, with the G9SP’s unique and intuitive programming software users can easily design, verify, standardize and reuse safety control. And because the G9SP isn’t hardwired into the control system, users will benefit from previously unavailable levels of safety system flexibility by quickly and easily reconfiguring the unit when new safety features are added to their set-up,” says Tony Rigoni, Business Development Manager, Omron STI.
If you would like more information about the G9SP safety controller or any of the products from STI Omron contact your ISC Companies representative or click the link below.
Permanent Magnet AC Motors Boasts Increased Efficiency & Other Benefits
When one thinks of a permanent magnet motor a DC motor
is what usually comes to mind. However recent advances in
materials and controls have brought this technology into the
realm of industrial motors with some decided advantages
including:
- Increased electrical efficiency (beyond that of NEMA “super-premium”)
- Increased power density
- Tighter speed regulation over a wider speed range
- Faster response due to lower rotor inertia
PMAC motors are inherently more efficient due to elimination of rotor conductor losses, lower resistance winding and “flatter” efficiency curve. Due to their synchronous operation, PMAC motors offer more precise speed control. PMAC motors provide higher power density due to the higher magnetic flux as compared with induction machines. Finally, Permanent Magnet motors generally operate cooler, resulting in longer bearing and insulation life.
PMAC motors not only are inherently more efficient but have a much better power factor (although system power factor...with a VFD...may not be as high as a motor-only induction machine). Since a permanent magnet rotor lacks conductors (rotor bars), there are no I2R losses.
Because PMAC motors are more efficient than induction motors they run cooler under the same load condition. This results in longer insulation and bearing life and reduces the amount of heat that goes into the operating environment. A general rule-of-thumb is that for every 10°C increase in operating temperature, insulation life is reduced by half; conversely every 10°C reduction in temperature doubles the insulation life.
The most obvious performance difference is that a PMAC motor rotates at the same speed as the magnetic field produced by the stator windings—it is a synchronous machine. If the field is “rotating” at 1800 rpm, the rotor turns at the same speed. An induction motor, on the other hand, is considered an asynchronous machine, as its rotational speed is slightly slower than the magnetic field’s “speed”. An asynchronous motor is said to have “slip” (the difference between the motor’s physical speed of, say, 1750 rpm, and its stator’s magnetic speed of 1800 rpm) and cannot produce torque without this difference in speed, as the rotor is constantly trying to “catch up” with the magnetic field. The synchronization of PMAC results in improved efficiency, better dynamic performance and more precise speed control…a major benefit in positioning applications.
The main difference in construction of a permanent magnet AC (PMAC) motor from AC induction motors is within the rotor itself. In a squirrel cage induction motor, current is induced into the rotor from the field (stator) through the air gap, and conducted through aluminum (or other material) bars, which are most often die cast in the slots of the rotor laminations. In the case of a PMAC motor, the rotor itself contains permanent magnet material, which is either surface-mounted to the rotor lamination stack or embedded within the rotor laminations. In either topology, electrical power is supplied through the stator windings.
Another benefit of PMAC technology is (unlike in conventional AC induction motors) there are no “shared slots” in the rotor. This essentially eliminates the potential for phase-to-phase shorts. It also means shorter end turns which reduce waste and make more room in the housing for active material, contributing to enhanced power density (end turns do nothing to generate torque). Generally speaking, PMAC motors provide higher flux density than a comparable induction motor. This means that more power (torque) can be produced in a given physical size, or equal torque produced in a smaller package.
PMAC motors typically have a wider speed range than AC Induction machines. However the number of poles may be different for the motors being compared and speed range is also a function of the drive being used so it is best to check with the manufacturer about your specific speed range. PMAC motors are suitable for Variable and Constant Torque applications. The VFD and application parameters will dictate to the motor how much torque to produce at any given speed. The flexible design makes PMAC motors a great choice when variable speed operation and ultra-high motor efficiency are required.
Servo motors are very similar to PMAC motors but use special controllers (amplifiers) and special feedback to control position rather than just speed. The price for servo systems is quite high…often 10-20 times that of an equivalent rated induction motor. Applications requiring “near servo” performance may be excellent candidates for PMAC motors, as the cost to performance ratio may be much more beneficial to the user.
Drives used with PMAC motors should be designed for use with permanent magnet machines. This is included in the specification for the drive and there is often a parameter to set to tell the drive that the motor attached is a PM motor. Some drives, not specifically designed for PM machines, will run and control a PM motor but performance will not be as high. It is possible to damage the motor or drive if the drive is not set up properly or are mismatched.
If you would like to learn more about PMAC motor technology contact your ISC Companies representative or click the link below.
