Description

TCC-80I Port-powered RS-232 to RS-422/485 converters

Introduction

The TCC-80/80I media converters provide complete signal conversion between RS-232 and RS-422/485, without requiring an external power source.

The converters support both half-duplex 2-wire RS-485 and full-duplex 4-wire RS-422/485, either of which can convert between RS-232’s T x D and R x D lines.

The automatic data direction control is provided for RS-485. In this case, the RS-485 driver is enabled automatically when the circuitry senses the T x D output from the RS-232 signal. This means that no programming effort is required to control the transmission direction of the RS-485 signal.

Features and benefits

• External power source supported but not required
• Compact size
• Converts RS-422, and both 2-wire and 4-wire RS-485
• RS-485 automatic data direction control
• Automatic baud-rate detection
• Built-in 120-ohm termination resistors
• 2.5 kV isolation (for TCC-80I only)
• LED port power indicator.

Port Power over RS-232

The RS-232 port of the TCC-80/80I is a DB9 female socket that can connect directly to the host PC, with power drawn from the TxD line. Regardless of whether the signal is high or low, it can obtain enough power from the data line. However, external power can be used if the handshake line is not available, if the serial cable is too long, or if the RS-232 device is a low-power device. For external power, a five to twelve VDC power supply can connect using an adapter or a USB power cord.

Port Power Dissipation

When installing a TCC-80 or TCC-80I converter, it is important to pay attention to power consumption, RS-232 cable length, and RS-422/485 transmission distance. In general, both of them obtain 50 mW of power from the power source. Standard PC COM ports can provide 70 to 90 mW of power if the T x D, RTS, and DTR lines are connected. Moreover, the RS-232 cable should be shorter than 15 m (@ 9600 bps) to ensure that less power is lost from the host/device to the TCC-80. The remainder of the supplied power can use for transmitting the RS-422/485 signal.

Port Power and Optical Isolation

The RS-232 port of the TCC-80/80I is a DB9 female socket that can connect directly to the host PC, with power drawn from the T x D line. Electrical 2.5 kV isolation for the TCC-80I can achieve with a photo coupler that transforms the electrical signal into light, and then re-transforms the light back into an electrical signal on the other side. In this way, the two electrical circuits are completely isolated from each other. This also protects the devices from ground loop currents, reduces damage caused by data loss, and prevents damage to the communication interfaces.

 

LED Port Power Indicator

It’s easy enough to test the serial device with a multimeter to determine that the serial device will provide enough power to the media converter. However, it’s even easier to let the TCC-80I test the device for you. Simply connect the TCC-80I to the device’s RS-232 port and set the SW4 switch to Test mode. If the port power LED indicator lights up, the TCC-80I is receiving enough power. If the LED does not light up, you will need to attach an external power source to this.

 

Serial interface

• Connector : Terminal block
• No. of ports : 2
• Serial Standards : RS-232, RS-422, RS-485
• Isolation : DB9: 2 kV
• RS-485 Data Direction Control : ADDC (automatic data direction control)
• Terminator for RS-485 : N/A, 120 ohms, 120 kilo-ohms
• Baud-rate : 300 bps to 115.2 kbps

Serial signals

• RS-422 : Tx+, Tx-, Rx+, Rx-, GND
• RS-485-4w : Tx+, Tx-, Rx+, Rx-, GND
• RS-485-2w : Data+, Data-, GND
• RS-232 : T x D, R x D, GND

Power parameters

• Input current  : TCC-80: 30 mA @ 5 to 12 VDC
  TCC-80-DB9: 30 mA @ 5 to 12 VDC
  TCC-80I: 20 mA @ 5 to 12 VDC
  TCC-80I-DB9: 20 mA @ 5 to 12 VDC
• Input voltage : 5 to 12 VDC
• No. of Power Inputs : 1
• Overload Current Protection : supported
• Source of Input Power : Power input jack

Physical characteristics

• Housing : plastic top cover, metal bottom plate
• IP rating : IP30
• Dimensions : TCC-80/80I: 42 x 80 x 22 mm (1.65 x 3.15 x 0.87 in)
  TCC-80-DB9/80I-DB9: 42 x 91 x 23.6 mm (1.65 x 3.58 x 0.93 in)
• Weight : 50 g (0.11 lb.)
• Installation : desktop
• Warranty : 5 years

Warranty

Warranty Period : 5 Years.

Additional information

Brand	moxa
Connector	Terminal block
Signal	RS-422 : Tx+, Tx-, Rx+, Rx-, GND RS-485-4w : Tx+, Tx-, Rx+, Rx-, GND RS-485-2w : Data+, Data-, GND RS-232 : T x D, R x D, GND
Power Consumption	TCC-80I: 20 mA @ 5 to 12 VDC
warranty	5 years