Siemens Servomotors – Asynchronous 1PH, 1PL

By CNC Design Pty Ltd

Dynamic power packs for main drives -

Our induction servomotors are predestined for applications where the main focus is on continuous, smooth running operation of axes: They are ideal as the main motor for presses, as roll drive in printing and paper machines, in textile and plastics machines, in all kind of winder applications, in machine tool spindles as well as in cranes and hoist applications. They cover a power range from 2.8 to 1340 kW and can address almost any application.

The wide range of motion control tasks in mechanical and plant engineering results in an equally wide range of requirements profiles for electrical drives. While inexpensive standard induction motors are sufficient for pumps and fan applications, sophisticated synchronous or induction motors developed specially for converter operation are needed to fulfil tasks at the other end of the performance scale. Extreme duty cycles, short rise times, as well as a high level of accuracy regarding speed, torque, and positioning represent typical performance requirements for ensuring maximum dynamic response and drive quality. In modern drive systems, it is the power packs themselves in the form of compact synchronous and induction motors that need to fulfil increasingly stringent requirements.


Our induction servomotors/ spindles have been designed to be fed from drive converters. They are more compact and rugged than conventional squirrel-cage induction motors and offer a high level of concentricity for smooth operation. For variable-speed operation, they have an incremental encoder; however, these motors can also be supplied with integrated absolute encoder for positioning applications. In more basic applications, operation is possible without having to use an encoder. An optional holding brake allows the drive to be reliably held at standstill without requiring any power input. Further, as rare-earth magnets have not been used, these motors are more favourably priced than synchronous servomotors – this certainly pays off even more with increasing motor power.


1PH7 - the universal one

The first choice for continuously operating axes with power ratings from 3.7 up to 385 kW is the 1PH7 motors with degree of protection IP55 (TEFC): They have an enormous acceleration capability up to a maximum of 12,000 rpm thanks to the high overload capability; they are equipped with a separately driven fan to ensure sufficient cooling – even at zero speed. In addition to the various encoder options these motors are also available with a holding brake.


1PH4 – for use in extreme environmental conditions

We recommend our water-cooled 1PH4 motors in degree of protection IP65 if air cooling is not possible as a result of extreme ambient conditions – such as high temperature, dust, dirt or an aggressive atmosphere. They also are favourable if space is restricted – especially if the water and necessary piping is available on-site anyway.


1PL6 – the extreme compact power pack

1PL6 motors are unbeatable when it comes to cost-efficiency and power if the ambient conditions allow open-circuit air-cooling motors to be used. These compact three phase motors, in shaft height 180 to 280 mm have been designed according to IEC 6034-5 with degree of protection IP23 (DPFC). The stators and rotors are open-circuit cooled. This motor cooling permits power ratings up to 630 kW.


Special versions for special applications

Our induction motors are also available in special versions – for instance as 1PM4/1PM6 motors with hollow-shaft for use on machine tool spindles. For motion control applications in explosion protection zones, such as are found in the printing industry and in paint shops we offer 1PH7 with supplementary option for use in hazardous Zone 2 or Zone 22 (according to IEC).


A new generation for main drives: 1PH8

To further strengthen our standing in this area, Siemens has completely overhauled the current selection of main drives to develop a brand-new product spectrum offering a range of performance features specifically designed to cater for the requirements of modern mechanical and plant engineering. The new 1PH8 motor series is designed to offer maximum flexibility for any situation


The modular system allows you to combine 1PH8 motors to create any drive solution configuration. In applications requiring compact systems with a high dynamic response, for example, you can choose between induction or synchronous versions. If extreme ambient conditions or low noise levels are deciding factors, however, you can also choose between air or water cooling. A range of additional options for electrically or mechanically integrating the motors in systems ensure that you benefit from maximum flexibility.


1PH8 motors have been extended to include shaft height 80 in the lower output range and shaft height 355 in the upper output range. The complete product range, therefore, features a total of eight shaft heights offering maximum flexibility with different cooling types and designs. New shaft heights in conjunction with numerous winding designs allow flexible configuration in an output range extending from 2.8 kW to 1340 kW.


Thanks to the high degree of protection, bearings designed for a wide range of different requirements, a vibration-resistant design, and state-of-the-art materials, the new main drives from Siemens are extremely robust. The encoder system is integrated in the motors, which means that it is fully protected against mechanical damage as well as the ingress of particles and moisture. Whether as an incremental encoder with HTL technology, a high-resolution, optical incremental and absolute encoder, or as a compact hollow-shaft encoder, the integrated encoder system can fulfil any requirement.


A range of standard options is available allowing the new 1PH8 motors to be extended to cope with extreme application conditions. In this way, for example, shaft sealing rings can be used to seal transmission attachments or provide additional protection in oily environments. Mounted filter systems allow air-cooled versions to be used in environments with high dust content.


The new 1PH8 motors are multi-talented devices that can be configured as required thanks to a modular system. Depending on drive requirements, you can choose from a range of synchronous or induction motors, which are identical with respect to appearance and dimensions. A similarly wide range of cooling types is also available, such as closed/open air cooling, or water cooling. If exacting demands regarding the service life of the motor bearings need to be satisfied, you can choose between standard bearings, bearings for strong radial forces, "advanced lifetime" bearings, as well as performance bearings depending on the application.