Quatech Asynchronous Communications Adapter DSC-200/300 - Manual (Page 8)

1.1 Features
The standard DSC-200/300 implements each of its communication channels with
a 16750 UART and uses standard line driver and receiver components. For improved
performance and industrial-grade reliability.
1.1.1 "IND" Option --- Surge Suppression Upgrade
The "IND" upgrade provides the protection essential for reliable use in an
industrial environment. Each communication line has a surge suppressor capable of
sustaining up to 40A 20us peak transient surges, a clamping voltage of 30V and a peak
energy dissipation of 0.1 Joules.
Quatech DSC-200/300 User's Manual 8