DGH RS232/RS485 Converter Boxes

A1000 Series

The DGH A1000 series converter boxes convert RS232 communications signal levels to the correct electrical signals required by RS485. RS485 is recommended when many DGH modules, or other addressable devices, must be connected to a host computer over long distances. The A1000 converters allow communications bus lengths up to 4,000 feet and baud rates up to 115.2K baud using one twisted pair of wires.

RS485 allows bi-directional data on the same pair of wires, therefore some means of arbitrating the data direction is required. The A1000 converters automatically control the bus direction without the need for external handshaking signals from the host computer. Therefore, host software written for half-duplex RS232 may be used without modification. The RS485 bus control is completely transparent to the user.

The A1000 can also operate as an RS-485 repeater. RS-485 repeaters are required to extend communications bus lengths or allow more than 32 devices to be connected to a communications bus.

The A1000 mechanical dimensions are: 8.08"W x 2.50"H x 6.25"D.

A2000 Series

The DGH A2000 is a bi-directional RS232/RS485 converter. RS485 is recommended when many DGH modules, or other addressable devices, must be connected to a host computer over long distances. The A2000 RS232/RS485 converters allow communications bus lengths up to 4,000 feet and baud rates up to 115.2K baud using one twisted pair of wires.

The A2000 may also be used as an RS485 repeater. RS485 repeaters re-amplify the RS485 signal when transmitting >4000 feet. They also allow more than 32 devices to be connected to the RS485 bus.

Therefore, host software written for half-duplex RS232 may be used without modification. The RS485 bus control is completely transparent to the user.

The A2000 is DC powered: 10 to 3Vdc, unregulated.

A2400 Series

The A2400 is a bi-directional RS232/RS485 converter that provides RTS and CTS support. RTS (Request-to-Send) and CTS (Clear-to-Send) are handshaking signals for where data flow must be synchronized to a communications device, such as a radio or leased line modem.

The A2400 is DC powered: 10 to 3Vdc, unregulated.

The A2400 series module can be mounted on a DIN-Rail using the MK-1 mounting kit.

DIN-190 Series

The DIN-191 and DIN-192 are an RS232/RS485 converter and an RS485 repeater.

DIN-191

The DIN-191 module transparently converts RS232 signals to those required by RS485 at all standard baud rates from 300 to 115.2K baud. Internal control circuitry automatically controls the flow of data on the RS485 bus. Therefore, the DIN-191 does not require external handshaking signals.

The DIN-191 is optically isolated from the RS232 input to the RS485 output by up to 500VAC and contains internal biasing and termination resistors for the RS485 bus.

DIN-192

The DIN-192 module transparently repeats RS485 signals at all standard baud rates from 300 to 115.2K baud. Internal control circuitry automatically controls the flow of data on the RS485 bus. Therefore, the DIN-192 does not require external handshaking signals.

The DIN-192 is optically isolated by up to 500VAC and contains internal biasing and termination resistors for each RS485 port.