Рук_п_16ДуДк (1031887), страница 19
Текст из файла (страница 19)
The LED is on when theconnection is good. If you suspect an I/O error, there are severalthings that could be causing the problem.• A loose terminal block• The power supply has failed• The module has failedSome Quick StepsWhen troubleshooting the ADAM-5000 series digital I/O modules,there are a few facts you should be aware of. These facts may assistyou in quickly correcting an I/O problem.• The digital output modules can not detect shorted or open outputpoints. If you suspect one or more points on an output module tobe faulty, you should measure the voltage drop from the commonto the suspect point.• Leakage current can be a problem when connecting field devices toI/O modules.
False input signals can be generated when theleakage current of an output device is great enough to turn on theconnected input device. To correct this, install a resistor in parallelwith the input or output of the circuit. The value of this resistorwill depend on the amount of leakage current and the voltageapplied but usually a 10K to 20 KΩ resistor will work. Insure thewattage rating of the resistor is correct for your applications.• The easiest method to determine if a module has failed is to replaceit if you have a spare.
However, if you suspect another device tohave caused the failure in the replacement module as well. As apoint of caution, you may want to check devices or power suppliesconnected to the failed module before replacing it with a sparemodule.7-6ADAM-5000AQuick Start ExampleQuick Start ExampleThis chapter provides guidelines to what is needed to set up andinstall a distributed ADAM-5000 network system. A quick hookupscheme is provided that lets you configure a single system before youinstall a network system.Be sure to carefully plan the layout and configuration of your networkbefore you start. Guidelines regarding layout are given in Appendix B:RS-485 Network.A.1System Requirements to Setup an ADAM-5000SystemBefore you setup an ADAM-5000 system, you can follow the steps toinstall I/O modules into the ADAM-5000 base.1. Align the module with the grooves on the top and bottom of thebase.2.
Push the unit straight into the base until it is firmly seated in thebackplane connector.3. Push-in the retaining clips at the top and bottom of the unit tosecure the module to the base.The following list gives an overview of what is needed to setup, installand configure an ADAM-5000 environment.• ADAM-5000/485 and I/O Modules• A host computer, such as an IBM PC/AT compatible, that canoutput ASCII characters with an RS-232C or RS-485 port• Power supply for the ADAM-5000 system (+10 to +30 VDC)• ADAM Series Utility Software• ADAM Isolated RS-232/RS-485 Converter (optional)• ADAM Repeater (optional)A-2ADAM-5000Appendix AHost ComputerAny computer or terminal that can output in ASCII format over eitherRS-232 or RS-485 can be connected as the host computer.
When onlyRS-232 is available, an ADAM RS-232/RS-485 Converter is required totransform the host signals to the correct RS-485 protocol. Theconverter also provides opto-isolation and transformer -basedisolation to protect your equipment.Power SupplyFor the ease of use in industrial environments the ADAM-5000systems designed to accept industry standard +24 VDC unregulatedpower. Operation is guaranteed when using any power supplybetween +10 and +30 VDC. Power ripples must be limited to 100 mVpeak to peak while the voltage in all cases must be maintained between+10 and +30 VDC.
When the systems are powered remotely the effectsof line voltage drops must be considered.All systems onboard switching regulators to sustain good efficiencyover the 10-30 V input range, therefore, we can assume that the actualcurrent draw is inversely proportional to the line voltage. The following example shows how to calculate the required current that a powersupply should be able to provide.Assume that a +24 VDC will be used to power an ADAM-5000/485 andfour ADAM-5017 input modules. The distance from Power supply tomodules is not so big that significant line voltage drop will occur.
OneADAM-5000/485 system and one ADAM-5017 module consume amaximum of 1.0 W (ADAM-5000) and 1.2 W (ADAM-5017). The totalrequired power will equal 1 W + 4 x 1.2 W = 5.8 Watts. A power supplyof +24 VDC should, therefore, be able to supply a minimal current of 5.8/ 24 = 0.25 Amps.Small systems may be powered by using wall-mounted modular powersupplies. Also when systems operate on long communication lines(>500 feet) it is often more reliable to power the systems locally withmodular power supplies. These inexpensive units can easily beobtained from any electronics retail store.The power cables should be selected according to the number ofsystems connected and the length of the power lines.
When using aADAM-5000A-3Quick Start Examplenetwork with long cables, we advise the use of thicker wire to limit theline voltage drop. In addition to serious voltage drops, long voltagelines can also cause interference with communication wires.POWER SUPPLY+10~+30 VDC++Vs-GNDINIT*COMDATA+DATA-Figure A-1 Power supply connectionsIt is advisable to use standard coding colors for the power lines:+Vs(R)RedGND(B)BlackCommunication WiringIt is recommended that shielded, twisted-pair cables that comply withthe EIA RS-485 standard be used with the ADAM-5000 network toreduce interference.
Only one set of twisted-pair cables is required toA-4ADAM-5000Appendix Atransmit both DATA and RTS signals. It is advisable that the following standard colors be used for the communication lines:DATA+(Y)YellowDATA-(G)GreenADAM Utility SoftwareA menu-driven utility program is provided for ADAM-5000 systemconfiguration, monitoring and calibration. It also includes a terminalemulation program that lets you easily communicate through theADAM command set.
(See Chapter 5, Utility Software)ADAM Isolated RS-232/RS-485 Converter (optional)When the host computer or terminal has only a RS-232 port, anADAM Isolated RS-232/RS-485 Converter, connected to the host's RS232 port, is required. Since this module is not addressable by the host,the baud rate must be set using a switch inside the module. Thefactory default setting is 9600 baud.ADAM Repeater (optional)When communication lines exceed 4000ft (1200 meters) or the numberof ADAM-5000 systems connected is more than 32, a repeater shouldbe connected to expand the first segment. Up to 32 repeater modulescan be connected allowing connection of up to 256 ADAM-5000systems.
As with the converter module, the repeater module is notaddressable by the host and the baud rate must be set by changingthe switch inside the module. The factory default setting is 9600 baud.A.2Basic Configuration Hook-upBefore placing the system in an existing network, the system should beconfigured properly. Though the system is initially configured at thefactory, it is recommended you check that the baud rate is set correctly.ADAM-5000A-5Quick Start ExampleDefault Factory SettingsBaud rate: 9600 Bits/sec.Address: 01 (hexadecimal)The basic hook-up for system configuration is show below:13-CHANNEL RTD INPUT17-CHANNEL T/C INPUT18-CHANNEL ANALOG INPUT16-CHANNEL DIGITAL INPUT14-CHANNEL ANALOG OUTPUT16-CHANNEL RELAY OUTPUT18-CHANNEL RELAY OUTPUT16-CHANNEL DIGITAL OUTPUTFigure A-2 ADAM-5000 system hook-up and configurationThe following items are required to configure an ADAM-5000 system:a personal computer with RS-232 port (baud rate sent to 9600) and theADAM utility software.Configuration with the ADAM Utility SoftwareThe easiest way to configure the ADAM system is by using theADAM utility software.
The easy-to-use, menu driven software willguide you through every step of the configuration process. (SeeChapter 5, Utility Software).A-6ADAM-5000Appendix AConfiguration with the ADAM Command SetADAM systems can also be configured by issuing direct commandfrom within the terminal emulation program that is included with theADAM utility software.The following example guides you through the setup of an analoginput module. Assume that an ADAM-5018 Thermocouple Inputmodule in slot 1 on an ADAM-5000/485 system still has its defaultsettings (baud rate 9600 and address 01h).
The system is first requested to send its default settings and then reconfigured.Note:An analog input module requires a maximum of 7seconds to perform auto calibration and ranging afterit is rebooted or powered on. During this time span,the module cannot be addressed to perform anyother actions.Example:Make sure that the module is properly connected as shown in Chapter4, Figure 4-3.
Power up all the connected devices, start the terminalemulation program, and issue the following command:$01S1B(cr)This command requests the module in slot 1 of the ADAM-5000system at address 01h to send its configuration status!010500The module of the system at address 01h responds that it is configured for an input range of ±2.5 V, integration time of 50 ms (60 Hz),format = engineering units and no checksum checking or generation.To change the configuration setting of the analog input module, thefollowing command is issued:$01S1A0F00(cr)$ = change configuration01 = target module at address 01ADAM-5000A-7Quick Start Example0F = set input range to type K thermocouple00 = set data format to engineering units, 50ms (60Hz)(See Chapter 6, Command Set for a full description of the syntax of theconfiguration command for an analog input module)When the module received the configuration command it will respondwith its new address:!01(cr)Wait 7 seconds to let the new configuration settings take effect beforeissuing a new command to the module.Note:All reconfiguration except changing of baud rate andchecksum values can be done dynamically, i.e.
themodules need not be reset. When changing baudrate or checksum, these changes should be made forall connected devices. After reconfiguration, allmodules should be powered down and then poweredup to force a reboot and let the changes take effect.See the next section for a strategy for changing baudrate and or checksum for an entire network.A.3 Baud Rate and ChecksumADAM-5000 systems contain an EEPROM to store configurationinformation and calibration constants. The ROM replaces the usualarray of switches and pots required to specify baud rate, input/outputrange, etc.
![](https://s.studizba.com/z.php?f=/templates/si/i/noavatar.png&w=100&h=100&t=1"){kind=avatar}
