This interface.is commonly used by teleprotection equipment for connection to telecom multiplexers.
The 21-170 converts the codirectional interface signals to a proprietary fiber optic protocol used for example by teleprotection equipment from ABB.
The converter is compatible with the FOT module in ABB’s tele protection terminals 550/560 for connecting the terminals to higher order networks. The 21-16xx converter running of its internal clock can also be used to directly interconnect protection equipment over leased lines using electrical E1 modems as SHDSL and alike.
The modem 21-1601 and 21-1651 from Fibersystem are combined fiberoptic synchronous and asynchronous modem with four different interfaces:
- G.703 unbalanced 2Mbps,
- G.703 balanced Nx64Kbps,
- X.21
- RS-530, not mounted on products produced after October 2006.
The modems are available in 2 versions:
- 21-1601 runs on 110-230 VAC , +/- 20%, power supply.
- 21-1651 runs on 48-250 VDC, +/- 20%, power supply.