Ident System CIS - EUCHNER GmbH + Co. KG - #4

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4 General Subject to technical modifi cations; no responsibility is accepted for the accuracy of this information. Inductive Ident Systems CIS Applications Inductive ident systems are used for the non-contact identifi cation of products such as tools, product carriers or containers in the entire manufacturing and logistics sector. The data carriers for the ident systems CIS are mostly programmed with a unique sequential number. The product is identifi ed at a read station using this number and the related production data are then assigned to the product. The data carriers are read using a completely wear-free inductive coupling. The read heads and data carriers are of robust design, have a high degree of protection and are designed for harsh industrial usage. The ident system will also work without problems when subject to dirt and moisture. System overview and function The ident system CIS essentially comprises the following components: Data carrier Read-only station or read/write station with data interface The ident systems CIS3, CIS3A and CIS3A-Mini are very similar with regard to the interfaces to the higher level control system. As a result the integration into the control system is similar. There are differences, on the one hand, in the design of the antenna and, on the other hand, in the design of the components. The special features and advantages of the individual systems as well as the related system components are divided into separate sections for the systems CIS3, CIS3A and CIS3A-Mini. The components for the different ident systems CIS3, CIS3A and CIS3A-Mini must not be mixed between the systems, i. e. a CIS3 read head is not suitable for reading a CIS3A data carrier. The read stations and read/write stations for the CIS3 and CIS3A are fi tted compactly in one housing. In the case of the CIS3A-Mini the stations are split in two for space reasons, that is interface adapter and antenna are connected via an antenna cable. Power is supplied to the transponder and the data are transferred between the read/write station and the data carrier without using any contacts. The CIS ident system operates on the principle of inductive coupling in the near fi eld, based on a carrier frequency of 125 kHz. This standard frequency at the low end of the frequency band used for RFID applications makes it possible, if necessary, to even install the data carrier fl ush in metal. However, it will certainly be of advantage if a non-metallic material is used in the immediate area around the data carrier. A memory chip and an antenna are fi tted in the data carrier, in various shapes (transponder). The E2PROM to which data can be written (programmable) retains the data in non-volatile form. For all standard data carriers used for CIS the following applies: Transponder without battery Robust encapsulated data carrier housing with degree of protection IP67 The read-only stations communicate with the higher level control system via a 4-bit parallel interface and the read/write stations via a serial interface. ƒô ƒô ƒô ƒô Integration for read-only operation The ident system CIS is mostly used in installation as a read-only system with the 4-bit parallel interface. The advantage of the parallel interface is simple integration into the control system and the transparent representation of the data. Quick and therefore low-cost integration into any type of PLC is possible. The 4 data wires, which are connected directly to the PLC via inputs and outputs (I/O), represent at a point in time a related hex digit using high/low levels (24 V/0 V). After the read station is switched on, the level on all 4 wires is initially high. If a data carrier now enters the operating distance of the read station, fi rst the data are automatically transferred from the data carrier to the memory in the read station and stored there temporarily. In the second step, the data are actively retrieved from the memory in the read station by the control system. For the second step it is no longer necessary for the data carrier to be in the read head's operating distance. The read station saves the data from a data carrier read until the next data carrier is fed to the read station or the read station is switched off and on again. In the case of the CIS3A-Mini it is also possible to delete the temporary memory in the read station via a reset pulse. If there is a data carrier in front of the read head, the data are transferred again automatically. In the fi rst step, it is signaled to the control system via the high level on the STROBE output on the read station that there is a data carrier in the operating distance and new data are available in the memory on the read station. The STROBE output is set to the high level when the fi rst 4 hex digits on the CIS3/CIS3A and the fi rst 8 hex digits on the CIS3A Mini are available in the memory on the read station. If in the case of the CIS3/CIS3A more than 4 hex digits are required in the application, it is necessary to wait long enough until all the digits have been transferred to the memory in the read station (see pulse diagram in the manual for the read station). If, for some reason (e. g. excessively high relative speed), it was not possible to read all the digits, on the output of the data Fhex is output as an error message from the point at which the data were no longer read from the data carrier. In the second step, the data can be retrieved from the temporary memory in the read station by the control system. A value between 0 and 15 is represented at a point in time via a combination of high/low levels on the data outputs on the read station using binary coding (high level on A=1, B=2, C=4, D=8). The fi rst digit from the data carrier is indicated immediately on the 4-bit data wire. Using pulses from the control system on the SKIP input on the read station, a maximum of 32 hex digits (16 bytes) can be read with the CIS3/CIS3A and 8 hex digits (4 bytes) with the CIS3A Mini. Reference is to be made to the pulse diagram in the manual for the read station for information on the timing of the pulses. If the SKIP input on the read station is maintained static at a high level, no data are transferred from the data carrier into the memory in the read station. By maintaining the SKIP signal at the high level prior to the entry of the data carrier in the operating distance, on the change in the SKIP signal to the low level the data can be read statically at this defi ned point in time. As long as the SKIP input is maintained at the high level, the STROBE output remains at the low level, even if there is a data carrier in the operating distance of the read head. The signaling that there is a read head in front of the read head must therefore be provided separately if you want to use this reading method. On the application of this method of control, a CIS3 data carrier can, for instance, approach the read head in the opposite direction to the arrow.