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Order toll-free in the U.S. 24 hours, 7 A.M. Monday to midnight Friday: 877-877-BBOX FREE technical support, 24 hours a day, 7 days a week: Call 724-746-5500 or fax 724-746-0746 Mail order: Black Box Corporation, 1000 Park Drive, Lawrence, PA 15055-1018 Web site: www.blackbox.com • E-mail: info@blackbox.com...
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FCC AND IC STATEMENTS FEDERAL COMMUNICATIONS COMMISSION INDUSTRY CANADA RADIO FREQUENCY INTERFERENCE STATEMENTS This equipment generates, uses, and can radiate radio frequency energy and if not installed and used properly, that is, in strict accordance with the manufacturer’s instructions, may cause interference to radio communi- cation.
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RS-232/485 CONVERTER NORMAS OFICIALES MEXICANAS (NOM) ELECTRICAL SAFETY STATEMENT INSTRUCCIONES DE SEGURIDAD 1. Todas las instrucciones de seguridad y operación deberán ser leídas antes de que el aparato eléctrico sea operado. 2. Las instrucciones de seguridad y operación deberán ser guardadas para referencia futura.
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NOM STATEMENT 10. El equipo eléctrico deber ser situado fuera del alcance de fuentes de calor como radiadores, registros de calor, estufas u otros aparatos (incluyendo amplificadores) que producen calor. 11. El aparato eléctrico deberá ser connectado a una fuente de poder sólo del tipo descrito en el instructivo de operación, o como se indique en el aparato.
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RS-232/485 CONVERTER TRADEMARKS Product names mentioned in this manual may be trademarks or registered trademarks of their respective companies and are hereby acknowledged.
Data Rate — Up to 115,200 bps Range — Up to 9 miles (14.4 km) Serial Interface — EIA/TIA-574 standard RS-232 DCE Connectors — IC620A-F: (1) DB9 female, (1) 5-position terminal block, IC620A-M: (1) DB9 male, (1) 5-position terminal block;...
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CHAPTER 1: Specifications CTS turns ON after the terminal raises RTS RTS/CTS Delay — 8 msec or “no delay” Carrier — The carrier is switch-selected either continuous operation or switched operation, controlled by RTS Surge Protection — 600 W power dissipation at 1 ms Temperature —...
RS-232/485 CONVERTER 2. Introduction 2.1 Description The RS-232/485 Converter (IC620A) is an ultra- miniature interface converter. Requiring no AC power or batteries for operation, the Converter supports asynchronous communication up to 115.2 Kbps over one or two unconditioned twisted pairs. Distances up to 15 miles (24 km) are attainable at lower data rates (1.2 Kbps, 19 AWG twisted pair).
CHAPTER 2: Introduction Six models are available: • DB9F/Term (IC620A-F) • DB9M/Term (IC620A-M) • DB9F/RJ-11 (IC623A-F) • DB9M/RJ-11 (IC623A-M) • DB9F/RJ-45 (IC624A-F) • DB9F/RJ-45 (IC624A-M) 2.2 Features • Operates asynchronously, point-to-point or multipoint, over 2 or 4 wires. • Up to 31 multipoint device drops in a polling environment.
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RS-232/485 CONVERTER • Twisted-pair connection via strain relief, RJ-11, or RJ-45. • Silicon Avalanche Diode surge protection. • A Transmitter On signal received at the RS-485 RCV connection will cause DCD output at the RS-232 connector to assert High.
CHAPTER 3: Configuration 3. Configuration The Converter is configured using two internal 4-position DIP switches. This section shows how to access the DIP switches, provides an overview of the factory-default settings, and describes all possible configuration options. For instructions on how to configure the Converter for specific applications, see Section 3.2.
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RS-232/485 CONVERTER Switch S1 Figure 3-1. Underside of the Converter’s main PC board, showing the location of DIP switch S1.
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CHAPTER 3: Configuration Switch S2 Figure 3-2. Top of the Converter’s daughterboard, showing the location of DIP switch S2.
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RS-232/485 CONVERTER To access the Converter’s internal PC boards, insert a small flat-blade screwdriver between the connector and the lip of the case and twist gently as shown in Figure 3-3. Figure 3-3. Opening the Converter’s plastic case with a small screwdriver.
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CHAPTER 3: Configuration Both DIP switch S1 and S2 are marked with individual switch numbers 1 through 4. Use these numbers, and the “ON” designation to orient the switch properly (see Figure 3-4). Use a small screwdriver or similar instrument to set each individual switch.
RS-232/485 CONVERTER 3.1.1 DIP S S1 S WITCH ETTINGS DIP switch S1 is used to configure receive impedance (termination), 2-wire/4-wire operation and “echo” enable/disable. Table 3-1 shows the factory-default settings for switch S1. Following Table 3-1 is a detailed description of each switch. Table 3-1.
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CHAPTER 3: Configuration S1-1: Receive Impedance (Termination) The setting for switch S1-1 selects the impedance of the input receiver. You may select either a “low” impedance of 120 ohms or a “high” impedance of 16 K ohms. By selecting the proper impedance for each drop, you can have up to 50 receivers in one application.
RS-232/485 CONVERTER S1-4: Echo Mode The setting for switch S1-4 determines whether the Converter echoes data back to the transmitting device (half-duplex mode only). S1-4 Setting Echo On Echo Off 3.1.2 DIP S S2 S WITCH ETTINGS DIP switch S2 is used to configure carrier control, RTS/CTS delay, and communication protocol.
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CHAPTER 3: Configuration S2-1: Carrier Control Method The setting for S2-1 determines whether the carrier is “Constantly On” or “Controlled by RTS.” This allows for operation in switched carrier, multipoint, and/or hardware handshaking applications. S2-1 Setting Controlled by RTS Constantly On NOTE When in Controlled mode, RTS must go negative to turn off the Transmitter and enable the Receiver.
RS-232/485 CONVERTER S2-3 and S2-4: “Transmit Off” Impedance Switches S2-3 and S2-4 are set together to determine whether the receiving device “sees” the impedance of the Converter’s transmitter as being “high” or “intermediate” when the transmitter is turned off. The “intermediate” setting is useful in half-duplex environments where the receiving device does not respond well to the “high”...
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CHAPTER 3: Configuration The switch settings generally needed to configure the Converter for these applications are shown in Table 3-3. NOTE Do not change switch settings until you have carefully read Section 3.1. Table 3-3. Typical Converter Applications Switch Point-to-Point Multipoint Settings 4W HDX...
RS-232/485 CONVERTER 4. Installation Once the Converter is properly configured, it is ready to connect to your system. This section tells you how to properly connect the Converter to the twisted-pair and EIA/TIA-574 interfaces, and how to operate the Converter. 4.1 Twisted-Pair Connection The Converter supports 2-wire or 4-wire communi- cation between two or more EIA/TIA-574 devices at...
CHAPTER 3: Configuration For your convenience, the Converter is available with several different twisted-pair interfaces: RJ-11 jack, RJ-45 jack, and terminal blocks with strain relief. The Converter is also available with DB25 male or female connectors. 4.1.1 T WISTED ONNECTIONS SING ERMINAL LOCKS...
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RS-232/485 CONVERTER 3. Strip the insulation on each of the twisted- pair wires about 1⁄8 inch. Figure 4-2. Stripping the insulation on the twisted-pair wires. 4. In a two-pair circuit, connect one pair of wires to XMT+ and XMT- (transmit positive and negative) on the terminal block, making careful note of which color is positive and which color is negative.
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CHAPTER 3: Configuration XMT+----------------------------------------RCV+ XMT- --------------------------------------- RCV- G-------------To Shield (Optional) RCV+-----------------------------------------XMT+ RCV - ----------------------------------------XMT- Figure 4-3. Two-Pair Crossover Cable. 6. In a single-pair circuit, use only the transmit (XMT) pair as shown in Figure 4-4. XMT+------------------------------------------XMT+ XMT - -----------------------------------------XMT- Figure 4-4. Transmit Pair. NOTE If there is a shield around the twisted-pair cable, it may be connected to “G”...
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RS-232/485 CONVERTER Figure 4-5. Wires connected to the terminal block. 8. Place the two halves of the strain-relief assembly on either side of the telephone wire and press together very lightly. Slide the assembly so that it is about two inches from the terminal posts and press together firmly.
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CHAPTER 3: Configuration 9. Insert the strain-relief assembly with the wire going through it into the slot in the bottom half of the modem case and seat it into the recess in the case. (If the telephone wire is too thin to be held by the strain-relief assembly, you will need to order a different-sized strain relief.
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RS-232/485 CONVERTER 10. Bend the top of the case as necessary to place it over the strain-relief assembly. Do not snap the case together yet. Figure 4-8. Closing the case. 11. Insert one captive screw through a saddle washer and then insert the captive screw, with the washer on it, through the hole in the DB25 end of the case.
CHAPTER 3: Configuration 4.1.2 T RJ-11 RJ-45 WISTED ONNECTION SING The RJ-11 and RJ-45 connectors on the Converter’s twisted-pair interface are pre-wired for a standard telco wiring environment. The signal/pin relationships are shown in Figure 4-9. RJ-11 Signal RJ-45 Signal 1--------------GND 1---------------N/C 2--------------RCV-...
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RS-232/485 CONVERTER Signal Pin# Pin# Signal 1--------------6 GND RCV- 2--------------4 XMT- XMT+ 3--------------5 RCV+ XMT- 4--------------2 XMT+ RCV+ 5--------------3 XMT+ 6--------------1 GND Connection to ground is optional. Figure 4-10. RJ-11 Cable (4-wire). Signal Pin# Pin# Signal 2--------------7 GND RCV- 3--------------5 XMT- XMT+ 4--------------6 RCV+ XMT-...
CHAPTER 3: Configuration Signal Pin# Pin# Signal XMT+ 3---------------3 XMT+ XMT- 4---------------4 XMT- Figure 4-12. RJ-11 Cable (2-wire). Signal Pin# Pin# Signal XMT+ 4--------------4 XMT+ XMT- 5--------------5 XMT- Figure 4-13. RJ-45 Cable (2-wire). 4.2 Wiring for Multipoint Circuits The Converter supports multipoint applications using a daisychain topology.
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RS-232/485 CONVERTER AISYCHAIN OPOLOGY Using a daisychain topology, you may connect several Converters together in a master/slave arrangement. Maximum distance between the units will vary based upon the number of drops, data rate, wire gauge, etc. Call Technical Support for specific distance estimates.
CHAPTER 3: Configuration 4.3 Connection to the EIA/TIA-574 Interface The Converter is designed to plug directly into the DB9 serial port of an EIA/TIA-574 DTE device (PC, laptop, host). If you must use a cable to connect the Converter to the DTE device, make sure that it is a straight-through cable of the shortest possible length—we recommend 6 ft.
RS-232/485 CONVERTER 4.4 Operating the Converter Once the Converter is properly installed, it should operate transparently—as if it were a standard cable connection. Operating power is derived from the RS-232 data and control signals; there is no ON/OFF switch. All data signals from the RS-232 and RS-485 interfaces are passed straight through.
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