Cable guide. for. High Performance Controllers and TeleControllers. Cable types and wiring guidelines

Transcription

1 Cable guide for High Performance Controllers and TeleControllers Cable types and wiring guidelines E31 Version 1.13

2 TABLE OF CONTENTS TABLE OF CONTENTS 2 FIGURES 3 1. User instructions on EMC 5 2. Connecting digital inputs and outputs Normally-ON/OFF switches or contacts Digital outputs A load on a relay output A load on a transistor output 7 3. Connecting analogue inputs 8 4. Connecting analogue outputs 8 5. RS232 connections Programming cables Communication cables Interface cable for RCC30: PP Interface cable for TC9: PP RS485 connections RS485: 2-wire system or 3-wire system? Setting EOL or BUS at RS485 communication Automatic RS4852 detection Communication cables V-NET through COAX cable V-NET through twisted-pair cable (RS485 connection) Versions book E31 20 HPC and Telecontroller 2

3 FIGURES Figure 1-1: Fault-free set-up 5 Figure 1-2: Fault-sensitive set-up 5 Figure 2-1: Connecting the digital inputs of the base module 6 Figure 2-2: Connecting digital relay outputs with a separate power supply 7 Figure 2-3: Connecting digital transistor outputs with a separate power supply 7 Figure 3-1: Connecting analogue inputs 8 Figure 4-1: Connecting analogue outputs 8 Figure 5-1: Programming cable HPC to PC-DB9 (PP-40) 9 Figure 5-2: Programming cable HPC to PC-DB25 (PP-41) 9 Figure 5-3: Programming cable handshake lines HPC to PC-DB9 (PP-80) 9 Figure 5-4: RS232 communication cable HPC to PC-DB9 (PP-45) 10 Figure 5-5: RS232 communication cable HPC to PC-DB25 (PP-46) 10 Figure 5-6: RS232 communication cable HPC to serial printer 10 Figure 5-7: RS232 communication cable HPC to E.D.&A. display, terminal or HPC (PP-30) 10 Figure 5-8: RS232 communication cable HPC to ESA terminal (PP-48) 11 Figure 5-9: RS232 communication cable HPC to HITECH PWS/terminal (PP-50) 11 Figure 5-10: RS232 communication cable HPC to HPC (DB25) (PP-47) 11 Figure 5-11: RS232 communication cable MODEM to HPC (PP-72) 11 Figure 5-12: RS232 communication cable MODEM to HPC (PP-73) 12 Figure 5-13: interface from PP-80 to RCC30 12 Figure 5-14: interface from PP-80 to TC9 13 Figure 6-1: RS485 bus connection between several HPCs 15 Figure 6-2: Faulty RS485 bus connection between several HPCs 15 Figure 6-3: RS485 communication cable with automatic detection 16 Figure 6-4: RS485 communication cable HPC to HPC (point-to-point) 16 Figure 6-5: RS485 communication cable HPC to HPC (bus) 16 Figure 7-1: V-NET bus connection between a number of HPCs 17 Figure 7-2: incorrect V-NET wiring 17 Figure 7-3: V-NET network with active HUB and REPEATER 18 HPC and Telecontroller 3

4 TABLES Table 1: Function setting of the serial port by means of the connecting block of the serial port 9 Table 2: Setting options for the EOL/BUS-jumper 15 Table 3: Setting an RS232 or an RS485 connection 16 Table 4: specifications for V-net through COAX cable 18 Table 5: specifications for V-net through twisted cable 19 HPC and Telecontroller 4

5 IMPORTANT REMARK: This manual is initially made for the HPCs (High Performance Controllers). The instructions also can be used for the Telecontrollers (Telecontrol Systems). 1. User instructions on EMC When mounting the HPC, it is recommended that a metal switchbox, provided with a metal base plate or back wall, is used. This base plate or back wall must be earthed according to the rules. The earthed terminals on the HPC base module should always be properly connected with the earthed terminal of the installation. Power lines and signal lines, both analogue and digital, must be placed in separate cable conduits, preferably made of metal. The wiring of analogue signals and communication lines must be provided with a properly earthed cloth. Signal and heavy current lines should not run parallel over long distances. In general, you should make sure that the distance between signal lines and possible interference sources is as far as possible. Signal lines should be kept as short as possible. All lines should be placed as close as possible to the metal base plate or back wall. The two wires of a signal line should be in the same cable bundle. This way, it is impossible for the wires to form some kind of antenna where an interference source can act on. A wrong method is represented in Figure 1-2 on page 5. The surface area of the plane formed by the central supply line and one of the two input signals is huge ( A= l1 * l2). The central supply line and the signal inputs form an antenna loop on which external interference sources may act. A correct setup is shown in Figure 1-1 on page 5. In this set-up, signal line and supply line are kept as close as possible to one another. The surface area of the resulting plane ( A= l1 * l2 or l1 * l2) is relatively small so that the influence of external interference sources is limited. L1 L1' L2 24V DC L1 L2 24V DC Figure 1-1: Fault-free set-up Figure 1-2: Fault-sensitive set-up Most cards are equipped with two-piece screw terminals, consisting of a male part and a female part. The male part is soldered to the printed circuit board. The female part on the other hand, is a detachable part with screw connections. It's best not to use solder on the end of the wire being clamped into the female connection block. The solder will start to flow slowly because of the pressure from the connection block, so the wire will come loose after a while. A wire wrapper is a much better solution. HPC and Telecontroller 5

6 2. Connecting digital inputs and outputs Because of the wide range of available sensors and switches, several connecting schemes are possible. It is important for you, the end user, to make the proper choice, depending on the type of sensor or switch. Below you will find some frequently used connecting schemes. When connecting the digital inputs and outputs, you should carefully observe the EMC user instructions. These instructions are thoroughly discussed in chapter Normally-ON/OFF switches or contacts R C To connect normally-on or normally-off switches, you should proceed as follows: Connect the 0V of an external 24V DC auxiliary supply with the 0V of the digital inputs The +24V is connected to one of the digital inputs through the switch. 24V DC Figure 2-1: Connecting the digital inputs of the base module If allowed by the entire system structure, you can use the HPC 24V supply and/or the output relay 24V auxiliary supply to feed the digital inputs. In this case, you need to provide an external loop for the 0V of the various circuits. 2.2 Digital outputs Most HPCs can be equipped with digital relay outputs or with digital transistor outputs. The area of application varies a lot from type to type. Relay outputs are more robust and are qualified to switch an AC load. Transistor outputs on the other hand, are faster and do not wear out. The way to connect the digital output depends on the type of digital output. It is important for you, the end user, to make the right choice, depending on the type of digital output. Hereinafter you will find a description of both types of digital outputs. The supply of the relays or transistor outputs is connected via a separate connection block on most HPCs. This supply is thereby independent from the main supply of the HPC. By adding this connection block to the emergency stop circuit, it is possible to build a very save installation. The ratification of the relays or transistors will always fall away if the emergency stop is pressed, whatever the state of the HPC program is at that moment. HPC and Telecontroller 6

7 2.2.1 A load on a relay output 24V DC 24V AC/DC In order to connect a digital relay output, you should proceed as follows: Connect the 0V of an external 24V DC auxiliary supply with the 0V of the digital output auxiliary supply Connect the +24V of an external 24V DC auxiliary supply with the +24V of the digital output auxiliary supply. Connect the load through the potentialfree contact of the relay output with a DC or AC source. Figure 2-2: Connecting digital relay outputs with a separate power supply If allowed by the entire system structure, you can use the 24V HPC supply and/or the 24V auxiliary supply of the output relay to feed the digital inputs. In this case, you need to provide an external loop for the 0V of the various circuits A load on a transistor output C4-1 C5-1 C6-1 24V DC Figure 2-3: Connecting digital transistor outputs with a separate power supply In order to connect a digital transistor output, you should proceed as follows: Connect the 0V of an external 24V DC auxiliary supply with the 0V of the digital output auxiliary supply Connect the +24V of an external 24V DC auxiliary supply with the +24V of the digital output auxiliary supply. Connect the +24V of an external 24V DC supply with the + terminal (collector) of the digital output. Connect the - terminal (emitter) of the digital output through the load with the 0V of the external 24V DC supply. It is also possible to collect the load between the +24V and the + terminal of the digital output. If allowed by the entire system structure, you can use the 24V HPC supply and/or the 24V auxiliary supply of the output relay to feed the digital inputs. In this case, you need to provide an external loop for the 0V of the various circuits. HPC and Telecontroller 7

8 When applying transistor outputs, you should pay particular attention to the polarity of the switch voltage and the switch current. Any surplus current, even for the shortest time, may cause some irrecoverable damage to the transistor output. The transistor outputs applied in this HPC are not resistant to short-circuits. 3. Connecting analogue inputs In order to connect an analogue input, you should proceed as follows: C R - + * Connect the 0V of an external analogue signal source to the 0V of the analogue input concerned. Connect the signal output of the signal source to the signal input of the analogue input. Always use two paired terminals of the analogue input to connect a signal source to the HPC. Figure 3-1: Connecting analogue inputs 4. Connecting analogue outputs + V - In order to connect an analogue output, you should proceed as follows: Connect the 0V of an external analogue load to the 0V of the analogue output. Connect the signal input (0-10V) of the load to the signal terminal of the analogue output. Figure 4-1: Connecting analogue outputs HPC and Telecontroller 8

9 5. RS232 connections 5.1 Programming cables IBM PC DB9 VR GND RXD TXD RTS CTS DSR DCD DTR GND TXD RXD PGM Figure 5-1: Programming cable HPC to PC-DB9 (PP-40) For programming the HPC by means of a PC with a DB9 connection for the serial port, you can use the connecting cable presented in the opposite figure. This connecting cable can also be found as product number PP-40 in the standard product lists. It's better to use a PP-80 instead of a PP-40(old cable). It has the same possibilities but can be used in combination with a modem too. IBM PC DB25 VR GND 7 RXD 3 TXD 2 RTS 4 CTS 5 DSR 6 DCD 8 DTR 20 1 GND 4 TXD 2 RXD 6 PGM For programming the HPC by means of a PC with a DB25 connection for the serial port, you can use the connecting cable presented in the opposite figure. This connecting cable can also be found as product number PP-41 in the standard product lists. Figure 5-2: Programming cable HPC to PC-DB25 (PP- 41) GND RXD TXD DTR CD DSR RTS CTS IBM PC DB9 VR GND TXD RXD CD/DSR DTR/RTS PGM Figure 5-3: Programming cable handshake lines HPC to PC-DB9 (PP-80) This cable is a new version of the PP-40 cable. In addition to the PP-40, it has 2 handshake lines. These extra connections are needed if a modem driver is installed on the programmer port. This cable can be used instead of a PP- 40 cable at all times. This connecting cable can also be found as product number PP-80 in the standard product lists. A DB25 to DB9 converter can be used on PC systems with a DB25 serial port. A connection between two terminals next to each other should always be made with a piece of wire. A drop of solder will crack as soon as the cable is used a few times. Table 1: Function setting of the serial port by means of the connecting block of the serial port Terminal 6 Not connected Connected to terminal 1 Function The serial port is set as a universal communication port. The serial port is set as a programmer port and cannot be used as a universal communication port. HPC and Telecontroller 9

10 5.2 Communication cables IBM PC DB9 VR GND 5 RXD 2 TXD 3 RTS 7 CTS 8 DSR 6 DCD 1 DTR 4 1 GND 4 TXD 2 RXD For data transfers between the HPC and a PC with DB9 connection for the serial port, by means of MODBUS or FUP, you can use the connecting cable presented in the opposite figure. This connecting cable can also be found as product number PP-45 in the standard product lists. Figure 5-4: RS232 communication cable HPC to PC-DB9 (PP-45) IBM PC DB25 VR GND 7 RXD 3 TXD 2 RTS 4 CTS 5 DSR 6 DCD 8 DTR 20 1 GND 4 TXD 2 RXD For data transfers between the HPC and a PC with DB25 connection for the serial port, by means of MODBUS or FUP, you can use the connecting cable presented in the figure opposite. This connecting cable can also be found as product number PP-46 in the standard product lists. Figure 5-5: RS232 communication cable HPC to PC- DB25 (PP-46) SERIELE PRINTER DB25 MA GND 7 RXD 3 DTR 20 1 GND 4 TXD 3 DSR For controlling a serial printer with DB25 connection, you can use the connecting cable presented in the opposite figure. Figure 5-6: RS232 communication cable HPC to serial printer HPC-DISPLAY-TERMINAL DB9 MA GND RXD TXD GND Figure 5-7: RS232 communication cable HPC to E.D.&A. display, terminal or HPC (PP-30) TXD RXD For controlling an E.D.&A. display or terminal by means of the HPC, you can use the connecting cable presented in the opposite figure. You can also use this cable for the realization of an RS232 point-to-point connection with the serial port (DB9) of another E.D.&A. HPC. This connecting cable can also be found as product number PP-30 in the standard product lists. HPC and Telecontroller 10

11 ESA Terminal DB25 MA GND 7 RXD 3 TXD 2 RTS 4 CTS GND 4 TXD 2 RXD For controlling an ESA terminal you can use the connecting cable presented in the opposite figure. This connecting cable can also be found as product number PP-48 in the standard product lists. Figure 5-8: RS232 communication cable HPC to ESA terminal (PP-48) HITECH Terminal DB25 VR GND 7 RXD 3 TXD 2 RTS 4 CTS 5 1 GND 4 TXD 2 RXD For controlling a HITECH PLC Work Station (PWS) or terminal, you can use the connecting cable presented in the opposite figure. This connecting cable can also be found as product number PP-50 in the standard product lists. Figure 5-9: RS232 communication cable HPC to HITECH PWS/terminal (PP-50) HPC DB25 MA GND 7 RXD 3 TXD 2 1 GND 4 TXD 2 RXD For realizing an RS232 point-to-point connection with the serial port (DB25) of another E.D.&A. HPC, you can use the connecting cable presented in the opposite figure. This connecting cable can also be found as product number PP-47 in the standard product lists. Figure 5-10: RS232 communication cable HPC to HPC (DB25) (PP-47) MODEM DB25 MA GND 7 RXD 3 TXD 2 CD 8 DTR 20 RTS 4 1 GND 2 RXD 4 TXD 3 CD/DSR 5 DTR/RTS For realizing a connection with a MODEM (with DB25 connector), you can use the connecting cable presented in the opposite figure. This connecting cable can also be found as product number PP-72 in the standard product lists. Figure 5-11: RS232 communication cable MODEM to HPC (PP-72) HPC and Telecontroller 11

12 MODEM DB9 MA GND 5 RXD 2 TXD 3 CD 1 DTR 4 RTS 7 1 GND 2 RXD 4 TXD 3 CD/DSR 5 DTR/RTS For realizing a connection with a MODEM (with DB9 connector), you can use the connecting cable presented in the opposite figure. This connecting cable can also be found as product number PP-73 in the standard product lists. Figure 5-12: RS232 communication cable MODEM to HPC (PP-73) This cable has a male DB9 connector at both ends which makes it possible to switch these two. Labels should be attached to both ends to prevent this. 5.3 Interface cable for RCC30: PP-90 The RCC30 is equipped with uniform two piece headers, including the connectors for the serial port. A special interface is available to convert the signals from a PP-80 cable to the header on the RCC30 (order code: PP-90). to PP80 DB9 female HPC RCC30 MTA 100 or IWT Pancon PGM 6 8 GSM/COM GND 1 RxD 4 TxD 2 CD 5 DTR 3 6 GND 5 TxD 4 RxD 3 DTR/RTS 2 CD/DSR Figure 5-13: interface from PP-80 to RCC30 Terminal 6 on the PP-80 cable is used to switch between programming and communication mode on most HPC systems. This is not true in combination with the RCC30. Terminal 8 on the RCC30 communication connector is used to switch between this connector and the optional GSM module. Terminal 6 of the PP-80 is connected to terminal 8 on the RCC30. Because of this, the serial port is switched from the GSM to the communication connector as soon as the PP-80 is present. It's also possible to switch between connector and GSM with the dip switch block on the RCC30! The programming and communication mode of the serial port on the RCC30 is set with a jumper on the RCC30. Detailed information is available in the manual of the RCC30: book E Interface cable for TC9: PP-91 The TC9 is equipped with uniform two piece headers, including the connector for the serial port. A special interface is available to convert the signals from a PP-80 cable to the header on the TC9 (order code: PP-91). HPC and Telecontroller 12

13 to PP80 DB9 female HPC TC9 Phoenix 6 poles DTR 3 CD 5 TxD 2 RxD 4 GND 1 1 CD/DSR 2 DTR/RTS 3 RxD 4 TxD 5 GND PGM 6 6 GSM/COM Figure 5-14: interface from PP-80 to TC9 Terminal 6 on the PP-80 cable is used to switch between programming and communication mode on most HPC systems. This is not true in combination with the TC9. Terminal 6 on the TC9 communication connector is used to switch between this connector and the optional GSM or PSTN module. Terminal 6 of the PP-80 is connected to terminal 6 on the TC9. Because of this, the serial port is switched from the GSM/PSTN to the communication connector as soon as the PP-80 is present. Detailed information about the function of terminal 6 is available in the manual of the TC9: book E47. HPC and Telecontroller 13

14 6. RS485 connections Read these instructions concerning RS485 connections: The max. length depends on the communication speed, the quality of the cable and the level of disturbance of the environment. With 9600 bps the max distance that can be bridged is about 1200 to 1500 metres. With speeds up to 9600 bps cables up to 450 metres can be used without terminators. In case that thin cables are used (0.10mm²/AWG28), the use of terminators can hinder the functioning, because these terminators take some much current so that the serial resistance of the cable causes a large loss of voltage. If long cables are used, using terminators is necessary. That is why thicker cables have to be used (0.26mm²/AWG24) so that the loss of voltage can be limited. In the RS485 installation instruction cable #9842 of the company BELDEN is used. 6.1 RS485: 2-wire system or 3-wire system? RS485 mostly is represented and used a 2 wire connection. In most of the applications the RS485 will perform excellently too with only 2 wires in the network cable. In the RS485 installation instruction the following remark is made: The signal flow return is via the earth connection of each housing or via a connection within the cable. It is not recommended to use both of them together. The RS485 network needs a 3 rd connection. This connection serves as a common reference for the RS485-interface of each device. In case of low speeds and short distances the lack of a 3 rd connection has no influence on RS485 because it is developed so that the reference can vary a bit. For example if 2 devices are situated 50 meter from each other and use the earth as return, there will be a difference in voltage in that piece of the earth (by currents that are always present in the earth). As long as the voltage is small enough, the network will work normally. With a lot of RS485 devices by which the network connection is made with 2 wires, the earth connection unintentionally is the 3 rd wire of the network. Disadvantages of the use of the earth as connection line: the danger of earth currents Problems that appear in case of a stroke of lightning in the installation environment. Because of the second reason E.D.&A. HPCs do not have a direct connection between earthing and the reference of the RS485 interface. To make a reliable RS485 network over a long distance, it is necessary to use a 3 rd wire in the RS485 cable. This 3 rd wire has to be connected to each device. It is not allowed to connect it with the earthing. HPC and Telecontroller 14

15 6.2 Setting EOL or BUS at RS485 communication HPC 1 HPC 2 HPC 3 HPC 4 Figure 6-1: RS485 bus connection between several HPCs HPC A HPC B HPC C HPC D If you want to establish a communication between more than 2 HPCs, you can no longer use of a so-called point-to-point connection, but you need to switch to a bus structure. A typical set-up is shown in Figure 6-1. This figure shows a set-up in which 4 HPCs are connected. Please note that the physical execution is to be realized in accordance with the schematic representation in the figure. From each HPC there is one connection to the previous HPC and one connection to the next HPC. Except for the first and the last HPC on the bus. They only make one connection with the second and the second last HPC on the RS485 bus respectively. Between two HPCs it is not allowed to make branches, nor is it allowed to make a direct connection from one HPC to three or more other HPCs. Figure 6-2 shows how you should not proceed. In this faulty set-up branches are used to connect HPCs A/C with HPCs B/D. Figure 6-2: Faulty RS485 bus connection between several HPCs In order for the bus connection to operate properly, the physical position of each HPC is to be set, i.e. at the end of the bus (like HPC 1 and 4) or somewhere in the middle (like HPC 2 and 3). On each card using RS485, a jumper is available to switch between EOL (End of Line) or BUS. This jumper must be put to EOL for the first and the last user of a bus. The jumper must be on BUS for the other devices of the bus. Table 2: Setting options for the EOL/BUS-jumper Settin g BUS EOL Meaning In the physical bus set-up, the HPC is neither the first, nor the last bus participant. In the physical bus set-up, the HPC is either the first or the last bus participant. HPC and Telecontroller 15

16 6.3 Automatic RS4852 detection HPC 1 DB9 MA L+ L HPC 2 DB9 MA Figure 6-3: RS485 communication cable with automatic detection L+ L- On a number of the apparatus of E.D.&A. is it possible to provide the DB9 connection block with RS232 and RS485. Some of these apparatus can switch over between these communication modes automatically. A wire between terminal 1 and terminal 7 is necessary to achieve this. It's always allowed to apply this connection, even if the apparatus does not support this automatic switchover. Table 3: Setting an RS232 or an RS485 connection Terminal 7 Not connected Connected with terminal 1 Physical connection Point-to-point connection by means of an RS232. Point-to-point or bus connection by means of an RS Communication cables HPC 1 DB9 MA L+ L HPC 2 DB9 MA 8 L+ 9 L- 7 1 For realizing an RS485 point-to-point connection with the RS485 serial port of another E.D.& A. HPC, you can use the connecting cable presented in the figure opposite. In this set-up the RS485 bus terminator of HPC 1 and HPC 2 must be set at End Of Line (EOL). Figure 6-4: RS485 communication cable HPC to HPC (point-to-point) HPC 1 DB9 MA L- L+ HPC 2 DB9 MA L- L+ HPC 3 DB9 MA L- L For realizing an RS485 bus connection with the RS485 serial port of 3 or more E.D.&A. HPCs, you can use the connecting cable presented in the figure opposite. In this set-up the RS485 bus terminator of HPC1 and HPC3 must be set at End Of Line (EOL). The RS485 bus terminator of HPC 2 must be set at BUS. Figure 6-5: RS485 communication cable HPC to HPC (bus) If you wish to include other apparatus in this bus connection, please read the connecting instructions in the user guides of the appliances concerned. The setting of the RS485 bus terminator depends of the apparatus and is discussed for each type individually. HPC and Telecontroller 16

17 7. V-NET through COAX cable In order to build up the network you should use COAX cable with the correct distinctive impedance. That is why the cable must be of the RG-62 type. This cable is slightly thicker than the COAX cable that is used for Ethernet networks. A standard cable with a length of 5 m may be obtained at E.D.&A (order number: PP-60). Make sure that the power wiring (220V/380V) is kept far enough from the network cable during the installation of the network cable. The net contamination that is usually present on the power wiring can radically disturb the communication. HPC 1 HPC 2 HPC 3 HPC 4 Figure 7-1: V-NET bus connection between a number of HPCs HPC A HPC B Figure 7-2: incorrect V-NET wiring HPC C HPC D A COAX cable should be used in a correct BUS topology: star-wired nodes are not allowed. Figure 7-1 gives an example of a network with 4 HPCs. A T-patch is used in HPC 2 & 3 to connect through the COAX. In HPC 1 & 4 the COAX is connected directly to the HPC. In this setting HPCs 2 & 3 are set to the BUS and 1 & 2 are set to the EOL. The setting in Figure 7-2 will not provide a correctly operating network. HPC C is connected through a branch to the T-patch and this is not allowed. The T-patch should be placed directly on the HPC. The setting BUS-EOL can be realized in 2 ways: By placing the jumper BUS-EOL in the right position on the network card. By using an external terminator (93) for V-NET /coax-networks. This terminator must be placed on the T-patch. The jumper stays on BUS. The advantage of the second procedure is that the HPCs can be mutually shifted without adjustment of the BUS-EOL jumper. Maximum 8 appliances can be mounted on one COAX cable. The cable may have a maximum length of 300m. If only 2 appliances are connected on one line then the cable may have a length of up to 450m. Active HUBs for ARC-NET networks can be used if several connecting points are needed. Various COAX lines can come to one active HUB. The individual COAX cables are still part of a BUS topology but the active HUB makes up the core of a star-wired node. A REPEATER for ARC-NET networks can be used if more than 300m should be crossed. In order to place this appliance the COAX cable can be divided in 2 parts, which can be 300 or 450m each. A COAX cable of up to 600m can be used between 2 active HUBs. HPC and Telecontroller 17

18 Figure 7-3: V-NET network with active HUB and REPEATER Table 4: specifications for V-net through COAX cable Maximum length of a network cable with 8 bus subscribers Maximum length of a network cable with 2 bus subscribers (point-to-point connection) Maximum length of a network cable between two HUBs Maximum number of bus subscribers on one COAX cable Maximum number of bus subscribers in one V-NET network Resistance value of the terminator 300m 450m 600m HPC and Telecontroller 18

19 8. V-NET through twisted-pair cable (RS485 connection) The communication cable does not belong to our delivery spectrum because of the large variety in mechanical demands for a communication cable. Cables of which the electrical specifications correspond with the requirements for V-NET through RS485 are manufactured among others by BELDEN, represented in the Benelux by ANIXTER (02/ ): type BELDEN Take into account that certain, not electric requirements, can influence the choice of a cable. Among other things think about the maximum tensile strength that the cable is allowed to be subject to, the producing of smoke in case of a fire or not, etc. All those matters are determined by instructions that apply in the field of the cable application. The usage of an inappropriate communication cable can have harmful influence on the accurate functioning of the communication. There will be a lot of communication errors at spacing above the allowed maximum. Maximum 20 network cards can be mounted on a network cable without the use of a REPEATER. Whatever the circumstances are, the total length of the network cable must not exceed 880m even with less than 20 network subscribers. The wiring of different network cards should be done in correct bus topology as described in point 6.2. The communication cable is provided with a shielding. This shielding should be connected at both ends of a cable section to each network card at terminals provided specifically for that purpose. Make sure that the power wiring (220V/380V) is kept far enough from the network cable during the installation of the network cable. The net contamination that is usually present on power wiring can radically disturb the communication. Table 5: specifications for V-net through twisted cable Maximum length of a network cable with 20 bus subscribers Maximum length of a network cable with 2 bus subscribers (point-to-point connection) Maximum number of bus subscribers on one twisted-pair cable Maximum number of bus subscribers in one V-NET network Resistance value of the terminator 800m 880m HPC and Telecontroller 19

20 9. Versions book E31 Version number Date Modifications 1.11 Initial version /05/2005 Added PP-90 and PP /7/2005 Manual can be used for HPCs and TeleControllers HPC and Telecontroller 20