The TCC-80I is the world's first high-speed, serial port powered converter with
2.5 KV isolation. The TCC-80I draws power from the attached RS-232 device, a
nd provides complete RS-232 to RS-422/485 interface conversion and electrical
 isolation protection. The TCC-80I converts between the RS-232 TxD and RxD li
nes and half duplex 2-wire RS-485, or full duplex 4-wire RS-422/485. The TCC-8
0I's outputs come with built-in 15 KV ESD surge protection to provide compreh
ensive protection against current overload. The TCC-80I also supports RS-485
automatic data direction control, in which the RS-485 driver is enabled by circuit
ry when the RS-232 TxD output is sensed. This means that no programming eff
ort is required to control the direction of the RS-485 signal.

Serial RS-232 Port Power and Optical Isolation
The RS-232 port of the TCC-80I is designed
 with a female DB9 socket to connect directl
y to the host PC, with power drawn from th
e combination of TxD, RTS, and DTR lines. T
he electrical 2.5 KV isolation of the TCC-80I
 is achieved by using a photo coupler to
transform an electrical signal into light, and
 then retransform the light back into an
 electrical signal on the other side. In this way, two electrical circuits are comple
tely isolated from each other. This also protects the devices from ground loop c
urrents, reduces damage caused by data loss, and prevents damage to the co
mmunication interfaces.

Patented LED Port Power Indicator
Although it is easy enough to use
amultimeter to determine whether
or not the attached serial port is
 able to provide enough electricity,
 abetter method is to use the built-
in "LED Port Power Indicator"
designed especially for the TCC-
80I. To do this, connect the TCC
-80I to the target RS-232 port,
and then turn the SW4 switch to
the right to Test mode. If the LED lights up, the TCC-80I is receiving enough
power. If the LED does NOT light up, you will need to attach the
external power cord to the TCC-80I.