New HEIDENHAIN rotary encoders with safe hollow-shaft connection

high availability and easier planning of systems and processes

HEIDENHAIN now offers its encoders of the ECN 400, EQN 400 and ERN 480 series also with a safe hollow shaft connection and mechanical fault exclusion. This rules out faults, such as slippage from a friction-type connection, that cannot be detected by the control. Machine and plant manufacturers can implement systems with high safety ratings with the new rotary encoders. Plant operators can always rely on the fact that their plants and processes run especially reliably and in a predictable manner.

The safe hollow shaft connection is available with the new rotary encoders for blind hollow shafts of 10 mm and 12 mm diameter. It is offered for encoders with the EnDat 2.2, DRIVE-CLiQ* and 1 VPP interfaces. This is achieved by simply pushing the hollow shaft of the rotary encoder with its clamping ring onto the measured shaft. On the encoder side, the combination of the clamping ring, the specially selected clamping ring material and an additional screw clamping provide a mechanically secure friction-type connection. The measured shaft must meet specified minimum requirements for tensile strength, surface pressure and surface roughness.

The new rotary encoders of the ECN 400, EQN 400 and ERN 480 series provide all the necessary prerequisites with this safe hollow shaft connection in combination with a safe control system to ensure the classification for safety-related applications in accordance with SIL 2 (according to EN 61 508) or performance level “d” (according to EN ISO 13849). The two absolute encoders ECN 400 (singleturn) and EQN 400 (multiturn) with serial interfaces also include all the information necessary for commissioning, monitoring and diagnostics. With the incremental encoder ERN 480, the machine and plant manufacturer can very easily meet the requirements of safety-oriented applications thanks to its mechanically safe hollow-shaft connection.

Thanks to their mechanically safe hollow shaft connection, the new HEIDENHAIN rotary encoders ECN 400, EQN 400 and ERN 480 are suitable for applications in machine tools as well as for pick-and-place machines in automation or for injection molding plants in plastics processing. In view of the high investment costs for such high-tech machines, owners expect high availability and predictability of their plants and processes. At the same time, legal safety regulations for the operation of the systems are increasing. In this environment, the new HEIDENHAIN rotary encoders ensure that position data are always correctly and exactly ascertained and transferred to the machine control unit.

In all rotary encoder variants, the universally applicable HEIDENHAIN PWM 20 phase meter together with the evaluation software ATS supports the user on site during diagnosis and installation. The safety functions can be triggered and checked via the PWM 20 during initial commissioning or when exchanging encoders for safety-related applications. If the encoder is connected directly to the PWM 20, a detailed analysis of the encoder functions is possible. If the PWM 20 is looped into the closed loop—if necessary by means of suitable test adapters—a real-time diagnosis of the machine or system is possible during operation. This provides meaningful data on the availability and function of the encoder.

*DRIVE-CLiQ is a registered trademark of SIEMENS AG.