| | | TS & VS - Single Point The SHG - TS & VS linear scales have a series of up to eight selectable reference markers spaced every 25.4mm, starting 78.5mm from the end of the scale. The reference point selected is dependent on the rotational alignment of the scale relative to the reader-head on installation. An installation LED, Bicolour green and red, is mounted on the reader head encoder face. Available with TTL output (TS) or ~IVpp output (VS) when used with SCC-200 converter. The MAG version contains a single point reference mark that can be applied at any point along the measuring length. Additional reference marks are available. TC - Distance-Coded The SHG - TC linear scales provide a unique output reference marker every 10 mm of movement along the length of the scale. This allows the absolute position value to be captured by the controller having moved over a maximum distance of 20 mm. This removes the requirement to traverse the full length of the scale to pick up the single point index and establish the alignment position. | | VM - MuApp Sinusodial When used with SCC - 100 (see page 22) VV - ~IVpp Sinusodial When used with SCC - 100 (see page 22) VP - ~IVpp Sinusodial When used with SCC - 200 (see page 23) A2 - RS232 Serial communication typically used to interface with PC control systems 'COM' port. This Electronics Industry Association (EIA) standard allows for data transmission from one transmitter to one receiver at data rates up to 20K bits/second and distances up to approximately 15m at the maximum data rate. A USB to Serial converter (Newall pt no 307-82340) is available to allow serial interface via a USB port. A4 - RS485 The RS485 standard is a multi-point communication network, which specifies up to 32 drivers and 32 receivers on a single 2-wire Bus. A key feature is the ability to address individual devices. Newall's Linear encoders are capable of being given and remembering a unique address tag which means multiple devices can be hung off the RS485 Bus. | | FANUC OUTPUT FORMAT AF - Absolute Fanuc This protocol is proprietary to Fanuc and available on all of their control systems. The controller makes a request for positional data and the encoder has to respond correctly with data within a strictly controlled time state. SSI OUTPUT FORMAT The SSI (Synchronous Serial Interface) is a patented absolute interface by Max Stegmann GmbH. Newall absolute encoders offer this interface implementing the 24bit Gray code or Binary positional encoding. An even parity checksum is available on the AS version. The Most Significant Bit (MSB) is transmitted first (D0). AB - Absolute SSI-Binary, 24 bit AG - Absolute SSI-Gray,24 bit AS - Absolute SSI-Gray, 24 bit with Even Parity (Parity is transmitted last as (D24) and is Even parity) | | |
| | | Binary is the position in decimal converted to its Binary equivalent and then expanded with additional zero's to fill the required data Example: 123456 (Decimal) = IIII000I00I000000 (Binary) If this is shown in a 24-bit data packet = 0000000IIII000I00I000000 Gray is a binary code that only varies by one bit per transition. Example: 0000 000I 00II 00I0 0II0 etc. So the position in decimal is converted to pure binary and then converted to its Gray-code equivalent. This has the advantage over binary in that the maximum reading error is a single step. | | |