The LD-01 is used in multidrop applications when a large numbers of units have to communicate with a main computer; for example in access control systems, weigh-scale systems or other types of measurement and data acquisition solutions. The LD-01 can be connected to equipment that uses the RS-232/V.24 interface. Westermo's ±10 mA balanced current loop (W1) transmission technique makes it possible to transmit data up to 18 km at low data rates. At shorter ranges transmission rates up to 38.4 kbit/s can be achieved. The LD-01 is also available in a ”by-pass” version. This model ensures that if a modem in the multidrop network should fail that modem will be by-passed, hence not effecting the communications between other units on the network.