Active Communication

Application:
Electrically isolated RS485 bus system

Overvoltage protection for RS485 ports:
The maximum permissible external differential voltage seen by the RS485 transceiver chips according to the data sheet of the semiconductor manufacturer is around +/- 12...14V. Voltages exceeding these values will inevitably result in destruction of the transceiver chips.

When using shielded cable, it is unlikely that such high differential voltages will occur, since extreme coupling onto the transmission line expresses itself as a rise in potential on all cable conductors.

When using the isolator on transmission lines outside of buildings or when the cabling conditions are unclear, use of the 66203 Isolator is recommended. This isolator model has built-in overvoltage protection, which limits the maximum occurring differential voltages to a harmless ±9V using fast protection diodes

 

Technical data:

Operating modes:		RS422 RS485 4-wire with automatic control RS485 2-wire with automatic control
Switching time:		Settable 10µs / 50µs for switching from data sending to receiving for RS485 automatic control (can be changed on request)
Overvoltage protection:		Differential voltage limiting by transil diodes to max. 9.2V at Imax = 20A and t = 10ms
Baud rate:		0..3 Mbaud
Data format:		any format
Signal lines:		RxD A/B, TxD A/B, CTS A/B, DTR A/B
Termination:		Connectable termination network for RS485 operation
Serial connections:		9-pin SUB-D adapters
Galvanic isolation:		Isolation voltage min. 1 KV DC between all terminals
Power supply:		12..24V DC/AC
Current consumption:		No-load: typ. 100 mA @12V DC, 50mA @24V DC Operating: typ. 140 mA @12V DC, 70mA @24V DC
Supply voltage connection:		Plug-in screw terminal, 5.08mm spacing Labeled "L+" and "M"
Ambient temperature:		Storage: -40..+70°C Operating in non-rowed installation: 0..+60°C Operating in rowed installation 0..+50°C
Permissible relative humidity:		0..95% RH (non-condensing)
Housing:		Plastic compact housing, 105x75x22mm
Weight:		approx. 100 g
Delivery:		1x RS422/RS485 isolator, Industry Please order power supplies separately as accessories

Product properties:

• Electrical isolated connection of RS422 devices and RS485 bus systems.
• Electrical isolation with an isolation voltage of 1kV avoids damage to the interfaces
• Automatic control in RS485 operation
• No re-configuration of transmission parameters required
• High transmission speeds of up to 3 Mbaud
• Wide supply voltage range up to 24V
• Shipped optionally with or without power supply:
  Please order power supplies as separate accessories.
• Conforms to standards both in office and industrial environments:
  • Increased noise immunity for industrial areas
  • Stricter noise emission for residential and commercial areas