How To Install Encoder
The connection and installation of rotary encoder shall strictly follow the instructions of each product. For general encoder installation guidelines, consider the following when installing the encoder:
- Installing different types of encoders
1.1 Solid shaft encoder
For solid shaft encoders, please note that different flanges and fastening flanges are synchronized on the mounting bracket.
The following are three ways to fix the solid shaft encoder:
*Fix the encoder and mounting bracket directly with the mounting hole at the end of the encoder flange.
*Use the mounting boss of the clamp flange to fix the encoder and mounting bracket through the clamp.
*Fix the decoder fixing and mounting bracket as eccentric clamps using clamps on the synchronizing flange.
1.2 Incremental encoder
For incremental encoders, setting the zero position through the marks on the shaft or cabinet and flange is helpful for the position assembly and use of the encoder. The fixed hole on the shaft in the through/blind hole coaxial encoder is equivalent to the zero mark position on the flange surface, that is, the mechanical zero position.
The plane and centerline of the solid shaft encoder shaft are aligned with the zero mark position(mechanical zero position) of the flange.
- Axis information
*The shaft shall be installed in the original state without any deformation.
*The torque of the screw at the top of the shaft is usually 0.6 Nm. Excessive torque will damage the screws.
*The encoder and shaft shall be installed in concentric position. In case of deviation, the mechanical load on the encoder shaft may exceed the rated range.
1.3 Coaxial encoder with blind hole
For coaxial encoders with blind holes, whether incremental or absolute, please note whether the shaft length is consistent with the depth of the shaft cover. For example, for dbs60, the length of the shaft should generally not be less than 15 mm or less than 40 mm. Atm60_SSI generally requires shaft lengths less than 15mm and less than 30mm.
1.4 Coaxial encoder with hole
For perforated coaxial encoders and incremental encoders, you can select the clamp ring on the same side or the other side and install the spring. This depends on the field installation environment. Please note whether it is more convenient to fix the clamp ring after fixing the spring.
1.5 Installing the absolute encoder
The mechanical installation forms of absolute rotary encoder include high-speed end installation, low-speed end installation and auxiliary mechanical device installation.
- Low speed end installation
The encoder is installed behind the reduction gear, such as the shaft end of the winch wire rope roller or the end of the final reduction gear. With this method, there is no gear return clearance, and the measurement is more direct and accurate.
This method can be used to measure remote positions, such as various lift equipment and transport trolley positions.
- Fast end installation
The rotary encoder is installed at the end of the rotary shaft of the power motor(or gear connection). The advantage of this method is high resolution. The multiline encoder has 4096 cycles, so it can make full use of the number of rotating rings of the motor to improve the resolution. There is a sufficient range within this range
The disadvantage is that moving objects with pitch error behind the reduction gear are usually used for one-way high-precision control and positioning, such as roll gap control.
In addition, if the encoder is directly installed on the high-speed port, the motor must vibrate slightly. Otherwise, the encoder is easily damaged.
- Installing the auxiliary machine
This method is usually used for gear rack, chain belt, friction wheel and rope receiving machinery.
- Possible problems when installing incremental encoder
2.1 Ignore cabinet installation
As we all know, in the process of installing precision instruments, it is easy to ignore the installation of cabinets. Select an authoritative dealer and pay attention to the overall details and wiring. The state of the enclosure must be maintained during installation.
2.2 Ignore All
In the installation process, people usually pay attention to the subsystem, which will lead to ignoring the acceptance of the entire sense. As a result, some cabling may be unsightly and the information panel may be irregular. Therefore, you need to fully understand the installation process.
2.3 Wiring
Cables must be laid correctly during installation and connection. The gap between wires should be set to less than the specified condition. If intersecting routing occurs, it is recommended to maintain the gap between the two wires under the specified conditions.
It is better to keep a certain distance from the wall when setting out wires. Technicians call this distance a safe distance. If necessary, PVC protection can be provided for the line. In addition, it is important to select qualified technicians.
- Precautions when installing single turn absolute encoder
Single turn absolute encoder measures each channel of the rotary optical drive to achieve unique coding. When rotating more than 360 degrees, the encoding will return to the original point, which does not conform to the principle of absolute encoding uniqueness. This code can only be measured within the 360 degree rotation range, which is called single turn absolute encoder.
When installing the single turn absolute encoder, please remember the following points:
*The encoder shaft and motor shaft shall be concentric as far as possible.
*The connection between encoder cable and extension cable shall be welded as far as possible to avoid poor contact caused by long-time oxidation and affecting signal collection.
*The encoder cable shall be separated from the connecting cable of equipment(such as high output equipment and converter) to avoid interference. The collected grayscale code can be converted to conventional binary code, and then the actual position/angle value can be mapped according to the conventional method.
*It is recommended that you choose an elastic shaft to reduce the installation accuracy or greatly improve the eccentric problem caused by wear.
*The encoder cable must be high-quality shielded twisted copper cable, which can reduce external interference and signal attenuation.
The rule of converting binary gray code into natural binary code is to keep the highest bit of gray code as the highest bit of natural binary code. The second high bit natural binary code is different from the second high bit gray scale code. The other bits of the natural binary code are similar to the second highest natural binary code.
- Rotary encoder installation procedure
*Prevent loosening due to vibration during use.
*When connecting the encoder, make sure that the maximum allowable values and deviations are not exceeded.
*If the screws around the encoder shaft are locked, they will not loosen during use.
4.1 Environment
Pay attention to whether there are interference sources around. Encoder is a kind of precision instrument which is easy to be interfered. If affected, it may have a negative impact on normal use. Temperature and humidity should also be concerned and understand the range of equipment requirements.
4.2 Axle load
When installing the rotary encoder, pay attention to the shaft load and clear the allowable range. Do not connect the DC or AC power supply when connecting the signal line. Otherwise, the output circuit may be damaged.
4.3 Connection
When connecting, the operator shall avoid rigid connection with encoder and use spring. In addition, the encoder must be gently pushed into the face group shaft during installation. Do not knock the encoder. Otherwise, the encoder may be damaged and affect the shafting.
- Installing servo motor encoder
When installing the servo motor encoder, various problems may occur, including mechanical and electrical problems. If these problems are not properly prevented or solved, the normal use and life of the encoder will be affected.
5.1 Electrical interface
The transmission speed and transmission distance of the electrical interface can be selected according to the specific application environment on site. The actual transmission distance and speed, encoder and communication cable installation are affected by the environment, grounding and cable materials.
5.2 Component layout
When the encoder is installed on site, frequency conversion, transformer, solenoid valve and other high-speed interference source equipment cannot be installed. In addition, a distance of 10 cm can be maintained or metal partitions can be installed. When installing the module communicating with the encoder, it is not allowed to install converter, contactor and other high interference source components or frequently disconnected switch components. In addition, a distance of 3cm can be maintained or metal diaphragms can be installed.
5.3 Grounding protection
The shielding layer of the cable shall be grounded at the signal receiving end to prevent the cable from being damaged by the leakage current between the two grounding points. If the shield wire of the cable is not properly grounded, connect and cut off the separate grounding wire.
For long distance grounding connection, yellow and green conductors shall be added between the product housing and the grounding as equal voltage compensation wires. The shielded cable must be connected to the metal shell of the electrical components(encoder or electrical cabinet) at both ends and connected correctly.