LDM422 ETC1 | Alldatasheet
Document overview
- Manufacturer or author: Provided By ALLDATASHEET.COM(FREE DATASHEET DOWNLOAD SITE)
- PDF pages: 4
Technical content
Features
\ COMPLETE ISOLATION WITH OPTICAL COUPLERS AND POWER DC-TO-DC CONVERTER \ INDUSTRIAL SURGE PROTECTION DEVICES \ SIX LED DIAGNOSTIC INDICATORS \ DC TO 19,200 BAUD AT 6000 FEET (1800M),
9600 BAUD AT 3 MILES (5KM)
\ REQUEST-TO-SEND, CLEAR-TO-SEND HANDSHAKE \ TRI-STATE OUTPUTS FOR MUL TIDROP
APPLICATIONS
\ SELECTION OF CONNECTORS \ WIDE OPERATION TEMPERATURE RANGE \` SOLDERLESS SCREW TERMINAL FIELD CONNECTIONS LDM422 Fully Isolated Limited Distance Modem, RS-232/422 Converter
Description
The LDM422 is a compact RS-232 to RS-422 converter which features a complete electrical isolation barrier and heavy duty electrical surge protectors. These devices feature a rugged aluminum enclosure small enough to mount on the back panel of typical computer equipment, saving valuable desk and floor space. Isolation is provided by optical couplers and a DC-to-DC converter. The RS-232 connection is through male or female EIA 25-pin connectors. The RS422 connections are made through convenient solderless screw terminals. The LDM422 series is designed for full duplex operation over two- wire pairs. Outputs are tri-state, allowing multidropping of up to 32 units. Hardware handshake is available over two separate wire pairs. Data rates are 75 to 19,200 baud. Six diagnostic LED indicators are provided (see Figure 1) for installation guidance and system troubleshooting. The RS-232 interface supports Request To Send, Clear To Send, Data Set Ready, Received Line Signal Detect, and Data Terminal Ready. A convenient null modem switch is provided for the data lines. The RS-422 interface supports Request To Send and Clear To Send on separate wire pairs. The LDM422 may be used to convert two sets of send and receive channels by using RTS and CTS circuits as the second data channels. Data rates are the same. The units use 12VAC from a wall-mounted transformer or ±12VDC to pins 9 (+) and 10 (–) of the RS-232 connector. Specifications Model LDM422 Baud Rate Range 0 – 19.2K Distance (miles) 1.14 3 4 5 7 Distance (km) 1.8 5 6.7 8.3 11.7 Maximum Multidrop 32. Reduced distances may be required when as Units many as 32 units are multidropped. No restrictions apply for distances of 1 mile (1.7 km) or less. Common Mode Surge: 750V Isolation Continuous: 500V Differential Mode (AC input) Surge Protection ANSI/IEEE C37.90.1-1989 (9 devices) (all RS-422 inputs and outputs) Channel Lines(1) TD, RD, RTS, CTS Control Lines(1) RTS, CTS, DTR, DSR, RLSD Modes Asynchronous 4-wire duplex, 2-wire half-duplex, 2-wire simplex Model LDM422 Null Modem Switch 1 (Reverses RS-232 pins 2 and 3) RS-422 Output Drive 20mA min/output RS-422 Input Impedance 6kΩ min/input Power: AC operation(2) 12VAC, ±10%, 10W screw terms 1 & 2 DC operation +11.5VDC to +17.0VDC @ 400mA on pin 9 -11.5VDC to -17.0VDC @ 400mA on pin 10 Operating Environment 0 °C to +70°C 0 to 95% relative humidity, noncondensing Dimensions 6.6 in x 2.1 in x 1.28 in (167.6 mm x 53.3 mm x 32.5 mm) Weight 7 oz (200 g) max PT3 and PT3E 11.0 oz (311.8 g) max MTBF(3) >100,000 hrs Notes: (1) TD = Transmit Data, RD = Receive Data, RTS = Request To Send, CTS = Clear To Send. DTR = Data Terminal Ready, DSR = Data Set Ready, RLSD = Received Line Signal Detect. (2) 120VAC and 220VAC power transformers are available. (3) Ground- benign environmental conditions (no salt atmosphere, <50°C ambient temperature). Dataforth does not authorize or warrant its products for use in life support/critical applications.
Figure 1. LDM422 Logic Diagram condition as ’Asserted’ input. The LDM422 conforms to EIA RS-232 and RS-422 specifications. communications cable. See Figures 1 and 3 for details.
2.10 (53.3) 1.852 (47.0) 0.175 0.010 (4.4 0.25) Figure 4. LDM422 Mechanical Drawing
Ordering Information
LDM422-P Male RS-232 connector LDM422-S Female RS-232 connector LDM422-PT Male RS-232 connector and U.S. power transformer LDM422-ST Female RS-232 connector and U.S. power transformer LDM422-PE Male RS-232 connector, Euro power transformer LDM422-SE Female RS-232 connector, Euro power transformer PT3 Wall mount U.S. power transformer, 120VAC PT3E Wall mount Euro power transformer, 220VAC