AC7 OPTO 22, AC7 Datasheet
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... AC7A/B USER’S GUIDE 43044 Business Park Drive, Temecula, CA 92590-3614 Phone: 800-321-OPTO (6786) or 951-695-3000 The information in this manual has been checked carefully and is believed to be accurate; however, Opto 22 assumes no responsibility for possible inaccuracies or omissions. Specifications are subject to change without notice. Opto 22 warrants all of its products to be free from defects in material or workmanship for 30 months from the manufacturing date code. ...
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... Overview ......................................................................................................................................... 16 Equipment Required for Installation ..................................................................................... 16 Mounting the AC7A/B ................................................................................................................ 16 Connecting AC Power to the AC7A/B .................................................................................... 17 Connecting the AC7A Other RS-232 Device .............................................. 18 Setting the AC7A/B RS-232 Jumpers (First group - near the 25-pin RS-232 connector) ............................................................ 20 RS-232 Handshaking Signals for Hardware Flow Control ...................................... 22 Setting the AC7A/B RS-422/485 Jumpers (Groups B and C) .......................................... 23 Connecting the AC7A RS-422/485 Device ...
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... Additional Technical Information ........................................................ 27 General Notes ................................................................................................................................ 27 Two-Wire RS-485 Mode ............................................................................................................ 28 Using Multiple AC7A/B Units on One Link .......................................................................... 30 Background ........................................................................................................................... 30 Description ............................................................................................................................. 30 Setup ......................................................................................................................................... 31 Biasing ...................................................................................................................................... 31 Termination ............................................................................................................................. 31 Wiring and Related Jumpers ............................................................................................. 31 Additional Jumpers .............................................................................................................. 31 Commonly Used RS-232 Signals ............................................................................................. 32 Using Protective Ground on AC7A/B ............................................................................. 33 Biasing and Terminating RS-422/485 ................................................................................... 33 Communication Jumpers ................................................................................................... 34 Troubleshooting ........................................................................................................................... 35 Glossary of Terms ......................................................................................................................... 36 RS-422/485 Cable Specifications ...
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... The converter operates as a full duplex device with transmission speeds up to 38,400 baud for distances up to 5,000 feet using two twisted pairs and a ground wire. Only “REV L” boards and above (AC7A) and “Rev C” boards and above (AC7B), can be used up to 115,200 baud. Earlier revision boards will operate up to 38,400 baud only. ...
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... The converter operates as a full duplex device with transmission speeds up to 38,400 baud for distances up to 5,000 feet using two twisted pairs and a signal ground wire. Revision L and newer AC7A/B’s can operate 115,200 baud. The maximum distance for 115,200 baud rate is 3,000 feet. ...
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... RS-422/485 full duplex over two twisted pairs and a signal ground. Additional twisted pairs for RTS and CTS. Also supports RS-485 2-wire mode. This requires user to build a custom RS-232 cable. Indicators Transmit, receive, RTS, CTS, and power. DIMENSIONS 6 AC7A/B User’s Guide Figure 1-2: AC7A/B Card Dimensions ...
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... If you are using the AC7A/B card to communicate with equipment other than Opto 22’s Optomux I/O, please see “Installing the AC7A/B for use with devices other than Opto 22’s Optomux I/O” later in this document. If you would like more detailed information, please see “Additional Technical Information”. ...
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... For safety purposes, a plastic insulating cover is provided for the power terminal block, and shouldbe installed after power wiring is completed. The AC7A/B has a terminal strip with three screw terminals for AC power. The AC power, which is supplied to the AC7A/B, should have three wires, two for AC power and one for earth ground (usually colored green). Connect the wire for earth ground (usually colored green) to the center screw terminal which is labeled GND ...
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... A standard RS-232 serial cable may be used to connect the AC7A/B adapter card to the PC. One end of the RS-232 cable must have a male 25-pin (DB-25) connector for the AC7A/B. The other end of the cable is for the PC, and will most likely need either a 9-pin (DB-9) female connector 25-pin (DB-25) female connector, depending on your computer ...
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... Figure 2-5: 25-Pin to 25-Pin, 3-Wire RS-232 Cable (made by user) Figure 2-6: 9-Pin to 25-Pin, 3-Wire RS-232 Cable (made by user) Note: Some serial cables that look like standard straight-through cables are actually null modem cables. The wiring diagram for a NULL modem cable is shown below: 10 AC7A/B User’s Guide ...
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... These two pins are tied together on a standard 25-pin to 9-pin straight-through cable 25-pin to 9-pin null-modem cable, pin 2 of one end is tied to pin 2 of the other end. INSTALLATION AC7A/B User’s Guide 11 ...
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... SETTING THE AC7A/B RS-232 JUMPERS (FIRST GROUP - NEAR THE 25-PIN RS-232 CONNECTOR) This group of jumpers is located right next to the DB-25 connector on the AC7A/B. The first 6 pins of the group are labeled PIN 2 OUT , PIN and PIN PIN 3 OUT . The rest are labeled by the letters A through H. ...
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... B AND C) These two jumper groups are located above the green 9-screw-terminal RS-422/485 connector. Group the left, and group the right. If the AC7A/B is being used in a standard Optomux network in either repeat or multidrop mode, install the jumpers as shown below. Figure 2-11: AC7A/B RS-422/485 Jumper Settings for use with Optomux Brain Boards More details on these jumpers are included in later sections of this manual ...
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... All conductors should be stranded #22 or #24 gauge, with a nominal impedance of 100 ohms and a capacitance of 12.5 pF/ft. The first pair of twisted wire connects the TO+ and TO- terminals on the AC7A/B to the FH+ and FH- terminals on the Optomux device (TO+ to FH+ and TO- to FH-). The second pair of twisted wire connects the FO+ and FO- terminals on the AC7A/B to the TH+ and TH- terminals on the Optomux equipment ...
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... The AC7A/B should now be ready to use with your Optomux network. After all wiring connections are made, and jumper settings have been checked time to supply AC power to the AC7A/B. The AC7A requires 115 VAC at 50–60 Hz. The AC7B uses 220VAC at 50–60 Hz. Once power has been supplied to the AC7A/B, the LED labeled PWR ON should become illuminated ...
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... OPTO 22’S OPTOMUX I/O OVERVIEW The AC7A/B was originally designed specifically to make it easy to connect any device with a standard RS-232 port to Opto 22’s Optomux I wire RS-422/485 mode. However, the AC7A/B can also be used as a general purpose, bi-directional RS-232 to RS-422/485 converter. EQUIPMENT REQUIRED FOR INSTALLATION • ...
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... For safety purposes, a plastic insulating cover is provided for the power terminal block and should be installed after power wiring is completed. The AC7A/B has a terminal strip with three screw terminals for AC power. The AC power that is supplied to the AC7A/B should have three wires, two for AC power and one for earth ground (usually colored green). Connect the wire for earth ground to the center screw terminal which is labeled GND ...
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... A standard RS-232 serial cable may be used to connect the AC7A/B adapter card to the PC. One end of the RS-232 cable must have a male 25-pin (DB-25) connector for the AC7A/B. The other end of the cable is for the PC, and will most likely need either a 9-pin (DB-9) female connector 25-pin (DB-25) female connector, depending on your computer ...
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... This section applies only to the 25-pin [DB25] RS-232 connection on the AC7A/B adapter card. Figure 3-5: 25-Pin to 25-Pin, 3-Wire RS-232 Cable (made by user) Figure 3-6: 9-Pin to 25-Pin, 3-Wire RS-232 Cable (made by user) Note: Some serial cables that look like standard straight through cables are actually null modem cables. ...
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... Moving the jumpers to the opposite position causes pin 2 on the AC7A/B RS-232 port to receive data, and pin 3 on the AC7A/B RS-232 port to transmit data. The jumpers may need to be moved to the other position, depending on whether or not you are using a standard straight-through cable null modem cable. The jumpers may also need to be moved depending on what type of device is being connected to the AC7A/B ...
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... Figure 3-9: Jumper Settings for Standard Straight-Through RS-232 Cable If you are using a NULL modem cable to connect the AC7A/B to your PC, you will need different jumper settings. The jumper settings for a NULL modem cable connecting an AC7A DTE RS-232 port) are shown below: Figure 3-10: Jumper Settings for use with an RS-232 Null Modem Cable More detailed information about these jumpers is available in “ ...
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... RS-422/485 device does: Install jumpers and H on the AC7A/B, and make sure the RTS ± and CTS ± lines are connected between the AC7A and the RS-422/485 device. Remove jumpers and G on the AC7A/B. ...
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... RS-422/485 devices require hardware flow control: Install jumpers E and G on the AC7A/B, and make sure the RTS ± and CTS ± lines are connected between the AC7A and the RS-422/485 device. Remove jumpers and H on the AC7A/B. This should work, although your particular equipment may require different settings ...
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... The first pair of wires is used for the transmit line. The second pair of wires is used for the receive line. The third pair of wires is used to connect the LOGIC GND of the AC7A/B to the COM terminal of the RS-485 device. Finally, the shield of the three pairs of twisted wire should be tied to earth ground at only one end of the shield. ...
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... One additional pair (pair #2) of wires is used to connect the LOGIC GND of the AC7A/B to the COM terminal of the RS-485 device. To use the AC7A/B in two wire mode, see the section titled Two-Wire RS-485 Mode (page 25). ...
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... The AC7A/B should now be ready to use. After all wiring connections are made, and jumper settings have been checked time to supply AC power to the AC7A/B. The AC7A requires 115 VAC at 50-60 Hz. The AC7B uses 220VAC at 50–60 Hz. Once power has been supplied to the AC7A/B, the LED labeled PWR ON should become illuminated ...
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... RS-232 port and exiting the RS-422/485 port RS-232 —> AC7A/B —> RS-422/485 The RX (Receive) LED will flash when the AC7A/B is receiving data into its RS-422/485 port (i.e., data is entering the RS-485 port and exiting the RS-232 port). ...
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... A few minor modifications must be made if you are using the AC7A/B in 2-wire mode. First, you will probably have to make your own custom RS-232 cable from the AC7A/B to the PC. This is to ensure that DTR (pin 20) on the AC7A/B’s RS-232 connector is not connected. If you are using a 25-pin port on the PC, then you’ ...
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... Second, install the three sets of jumpers on the AC7A/B as shown below. The shaded areas indicate where jumpers need to be placed. Figure 4-3: Three Sets of AC7A/B Jumpers Finally, connect FO+ to TO+, and FO- to TO- on the AC7A/B as shown below. Figure 4-4: Connecting the AC7A/B to the 2-Wire RS-485 Device ADDITIONAL TECHNICAL INFORMATION AC7A/B User’ ...
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... AC7A/Bs in the system, there will be multiple transmitters connected on the RS-422 portion of some or all of the AC7A/B’s. In order for this to work, each AC7A/B must be configured so that the RS-422 portion is setup in RS-485 mode. In other words, the RS-422 transmitters on the AC7A/B’s must be configured to be disabled when not actively transmitting in order to prevent interference with the other AC7A/B RS-422 transmitters. In addition, because the AC7A/B’ ...
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... Because of this, jumpers B4, B5, and B6 should be removed on all AC7A/Bs. Additional Jumpers In addition, since the RTS and CTS pairs are not used on the RS-422/485 side of the AC7A/ best to install jumpers C2, C4, C5, and C6 to prevent spurious LED activity. AC7A/B User’s Guide 31 ...
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... ADDITIONAL TECHNICAL INFORMATION COMMONLY USED RS-232 SIGNALS It is possible to effectively rewire certain pins of the RS-232 connector on the AC7A/B with the group of jumpers labeled A through H. These pins carry hardware handshaking signals which are commonly used to coordinate communication flow. RS-232 is a simple communication scheme that supports one device at each end of the RS-232 cable (two devices total) ...
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... Terminating resistors are needed at the two ends of this main line. Usually, this is done at the devices located at the physical ends of the line. Since the AC7A/B is usually located at the beginning or end of an RS-485 transmission line, the AC7A/B is usually the location for one of the termination resistors. However, a resistor doesn’ ...
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... However, only one pair of biasing resistors may be placed on an RS-485 network. Jumpers are provided on the AC7A/B to connect the biasing resistors to the RS-485 communication lines. If biasing is already accomplished at some other point on the RS-485 line, then the biasing resistor jumpers should be removed on the AC7A/B ...
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... RS-232 baud rate to make the LEDs flash slower, which will make the LEDs easier to see. If the TX LED is flashing, this means that RS-232 data is being received by the AC7A/B and re-transmitted out the RS-422/485 transmit (TO±) terminals. But because of the RS-422/485 loop back cable, the data is looped back from the RS-422/485 transmit (TO± ...
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... RTS – an abbreviation for Request to Send. RTS is a signal sent by the computer to tell the other device that the computer wants to send data to the other device. TD – an abbreviation for Transmit Data. Also sometimes shown TXD. This is the pin on a serial communication port where data is sent out to other devices. 36 AC7A/B User’s Guide ...
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... Belden P/N 8102 (with overall shield) • Belden P/N 9729 (individually shielded) • Belden P/N 8162 (individually shielded with overall shield) • Manhattan P/N M3475 (individually shielded with overall shield) • Manhattan P/N M39249 (individually shielded with overall shield) ADDITIONAL TECHNICAL INFORMATION AC7A/B User’s Guide 37 ...
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... APPENDIX A APPENDIX A Figure A-1: AC7A/B DB9 (J2) Connection Pinout 38 AC7A/B User’s Guide ...
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... I/O units installed — third-party devices installed (e.g., barcode readers) • Specific error messages seen PRODUCT SUPPORT 800-TEK-OPTO (835-6786) 951-695-3080 951-695-3017 support@opto22.com http://www.opto22.com AC7A/B User’s Guide 39 ...
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... AC7A/B User’s Guide ...