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LDM Modular Converter

Isolated Modular Converters and Line Drivers

LDM Heavy Duty Modular Converters / Line Drivers

  • Extend communication distances for computers, terminals, and other devices in hazardous industrial and institutional environments
  • Connect RS-232 devices to RS-422 and RS-485 devices
  • 5 models communicate over distances up to 12 miles (19.3km) using continuous dedicated wire pairs and standard RS-232, RS-422, or RS-485 protocols (LDM30/35/70/422/485)
  • 2 models feature fiber optic data links for total electrical isolation and operation up to 2.2 miles (3.5km) (LDM80/85)
Data communications in industrial and institutional environments can present special problems. Lines must be run over long distances, often ranging from thousands of feet to several miles, indoors and outdoors and from building to building. Such data communication systems must be able to function in the presence of electrical transients and noise, ground loops, power surges, and nearby lightning strikes. Our heavy duty industrial data communication products "harden" and protect these systems and can extend data communication networks for many miles without expensive cabling.

All Data Communication Products: Side-by-side specifications comparison

Model Description Max Data Rate Max Distance Notes
DCP DIN Rail Mount Converter and Line Driver Selection
DCP485 Fully Isolated DIN Rail RS-232 to RS-485 Converter/Line Driver 115.2kbps at 0.8 miles (1.3 km) 7 miles (11.3 km) at 1.2kbps DIN rail mounting, auto RS-485 line control
DCP35 DIN Rail Dual Port Signal-Powered RS-232 Line Driver 19.2kbps at 0.5 miles (0.8 km)
 7 miles (11.3 km) at 1.2kbps
 DIN rail
LDM Line Driver and Converter Selection
LDM30
 General Purpose RS-232 Line Driver
 57.6kbps at 0.5 miles (0.8 km)
 12 miles (19.3 km) at 1.2kbps
 Low cost
LDM35
 Signal Powered RS-232 Line Driver
 19.2kbps at 0.5 miles (0.8 km)
 7 miles (11.3 km) at 1.2kbps
 Port-signal powered
LDM70
 Fully Isolated RS-232 Line Driver
 57.6kbps at 0.5 miles (0.8 km)
 12 miles (19.3 km) at 1.2kbps
 Full isolation, DTR/RLSD handshake
LDM422 Fully Isolated RS-232/422 Converter 19.2kbps at 1 mile (1.6 km) 7 miles (11.3 km) at 1.2kbps Multidrop capable
RTS/CTS handshake
or 2nd data channel
LDM485 Fully Isolated RS-232/485 Converter 57.6kbps at 0.5 miles (0.8 km) 8 miles (12.9 km) at 1.2kbps Multidrop capable
RTS/CTS handshake
or 2nd data channel
LDM80
 Signal Powered Fiber Optic Converter 19.2kbps at 2.2 miles (3.5 km) 2.2 miles (3.5 km) at 19.2kbps Total electrical isolation, intrinsic safety
LDM85 Fiber Optic Converter 5M - 2.5Mbps NRZ TTL (100kbps RS-232/422) at 1.2 miles (2 km) 1.2 miles (2 km) at max data rate Multipoint optical loop, total electrical isolation
Documents
Overview of LDM Isolated Modular Converters and Line Drivers
3D CAD/STEP Files 3D CAD Models
LDM Module & Accessory 3-D CAD Models
Product Availability
Usually stock to 2-3 weeks

FAQ

Due to resource constraints on my computer, I'm unable to open the three dimensional CAD models provided on your website. Does Dataforth provide two demensional CAD models for download as well?
Two dimensional CAD models can be generated upon customer request. Please contact Customer Service for assistance.
Will the LDM85 work with LVTTL?
Because the high/low thresholds for 5VTTL and LVTTL are the same, the LDM85 will work with this standard.
Does the LDM85 come with a power supply?
All power supplies are sold separately from the LDM85. The PT3 and PT3E are compatible power supplies with the LDM85.
Is the LDM35 a suitable replacement for the LDM30?
Please observe the block diagram in the datasheets of the LDM35 and LDM30 modules. In the block diagram, you can see the direction of space current and mark current through terminals 3 and 4 (TD+ and TD-). Since these currents flow in the opposite direction between the LDM30 and LDM35, the LDM35 cannot be used to replace the LDM30. We recommend replacing the LDM30 with another LDM30, or you can use the LDM70 as a suitable replacement as well.
Can Dataforth provide calibration reports for modules I purchased?
Yes we can provide calibration reports for the modules that you purchased. You can either a) visit https://www.dataforth.com/TestDataReport.aspx to search for Test Report Datasheets by Serial Number or b) you can send us a list of model numbers and their serial numbers to support@dataforth.com

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