How to set programmable angle encoders

Some of the challenges facing system integrators, production engineers and service personnel when installing and adjusting encoders include setting the exact zero or middle point or the start and end points of measuring ranges. Components are frequently installed in such confined spaces that mechanical adjustment of the rotary encoder is impossible or extremely difficult. There is also often the need to reset angle sensors in the field in order to adjust for wear-related changes of the measured system. This should be easy and convenient to do and not require any complex aids.

A further issue that should not be underestimated is the wide variety of available applications that many customers have, and the numerous requirements these place on the encoders. While it is true that high-precision angle sensors are preconfigured with custom output characteristics and angle ranges, and are available at attractive prices ex-works, the procurement and storage of a range of different encoder variants has logistic and financial consequences.

Easy on-site configuration

To meet these challenges and create a high level of flexibility for customers, Contelec has developed simple, innovative 'setting features' that enable the on-site configuration of encoders based on Vert-X MH-C2 technology after installation. To enable parameterisation, the rotary encoders have two additional digital inputs (Set 1 and Set 2), which are used to set the sense of rotation (CW, CCW), index points (zero point or middle point) or start and end points as often as needed. This process is designed to be very easy. All that is needed is to connect the two input leads to ground in a specific sequence.

The configuration of the Vert-X MH-C2-based angle sensors with integral setting features simplifies installation and adjustment significantly. A key factor here is that installation in a machine is not restricted by mechanical tolerances or the angle position of the rotary encoder. This can be illustrated with the setting of the start and end points in the 'plough turn control' application (see illustration above). Once the angle sensor has been attached in any position, the plough is physically moved to its starting point and Set 1 is set to zero. In the next step, the plough is moved to its end position and the second input (Set 2) is connected to ground. This simple process sets the start and end points and ensures highly accurate adjustment of the encoder.

Customers benefit as follows:

• Easy, individual setting of the sense of rotation (CW, CCW), index points (zero or middle point) or start and end points on site and without any additional aids
• No mechanical adjustment of the rotary encoder is necessary (this saves time and cost, and results in highly accurate angle measurements even in systems that do not permit mechanical adjustment)
• Maximisation of measurement accuracy, even with wide installation tolerances
• Compensation of mechanical inaccuracies on the system being measured (component tolerances are eliminated)
• Easy compensation of mechanical wear by 'readjustment' in the field (resulting in improved quality)
• Reduction of the required number of encoder variants (simplified storage and reduced costs)
• High level of safety ensured by a standardised setting sequence and non-volatile storage of the settings
• Such encoders are also suitable for use in heavy-duty applications

Key performance characteristics

The Contelec Vert-X MH-C2 rotary encoders with integral setting features significantly simplify installation and adjustment of angle sensors.

tstart{c,75%}

tdata{Encoder types|Contactless and non-contacting rotary encoders}

tdata{Encoder size|From 22mm outside diameter}

tdata{Possible settings|Sense of rotation (CW, CCW); index point (zero point/middle point); start and end points}

tdata{Setting|Through two additional digital inputs; standardised setting sequence}

tend{}

Example: setting the angle range (start and end points) and sense of rotation

1. Turn the rotary encoder to the desired starting angle
2. Connect 'Set 1' input to GND
3. Within the specified time (tsetting), turn the rotary encoder to the desired end angle and connect the 'Set 2' input to GND
4. The angle range and sense of rotation (CW) have now been set and stored

Follow the link for more information about Contelec programmable angle encoders from Variohm-Eurosensor.