RS232 to RS422/RS485 or 20mA converter, KD485-STD
The KD485-STD is an interface converter/isolator only and is baud rate and character format independent. Its main application is in isolated conversion between RS232 and RS422. It can also drive a 2-wire RS485 bus if the RS232 host provides RTS Control. Requires a power supply in the range of 7-35 volts at typically less than 2 watts.
Versions:
RS232<>RS422/RS485 converter
RS232<>20mA isolated converter
RS232<>RS232 port isolator
RS422<>RS422 port isolator
Product variants
| Article Number | Product Name | |
|---|---|---|
| 1111-07-1920-232-00 + | KD485-STD | + Request quote |
| RS232<>RS422/485 industrial isolated converter, DIN-rail mounting | ||
| 1111-07-1920-232-03 + | KD485-STD-232-20mA | + Request quote |
| RS232<>20mA isolated coverter, DIN-rail mounting | ||
| 1111-07-1920-232-01 + | KD485-STD-232-232 | + Request quote |
| RS232<>RS232 port isolator, Rx/Tx/GND isolated coverter, DIN-rail mounting | ||
| 1111-07-1920-422-01 + | KD485-STD-422-422 | + Request quote |
| RS422<>RS422 port isolator, Rx/Tx/GND isolated coverter, DIN-rail mounting | ||
Description
The KD485-STD is an interface converter/isolator only and is baud rate and character format independent. Its main application is in isolated conversion between RS232 and RS422. It can also drive a 2-wire RS485 bus if the RS232 host provides RTS Control.
RTS Control is relevant only if you are converting to 2-wire RS485 (where the converter is a Master or a Slave) or to 4-wire RS485 (where the converter is a Slave). It is not required for RS422 which is a point to point system only and on which the driver is permanently enabled.
RTS Control is a method with which the RS232 device (typically a PC) tells an RS232-RS485 converter when it should enable its RS485 driver, i.e. when it should be transmitting. There is no technical reason why the converter cannot determine this by itself but it increases the cost of the converter. It also makes it sensitive to the baud rate and character length (the number of bits) and these therefore need to be configured somehow on the converter.
It can also act as a Master on a 4-wire "RS485" bus. Requires a power supply in the range of 7-35 volts at typically less than 2 watts.
Port 1 is RS232. Port 2 is RS422, RS485 or 20mA.
- Two serial ports (port type must be specified when ordering)
- DIN-rail enclosure with removable screw terminals; fits 35mm symmetric rails
- 29mm width on DIN rail
- 7-35V DC powered
- Three-way isolated (Port 1, Port 2 and power input are mutually isolated)
- Data flow indicator LEDs
- 0-115200 baud, low-emission drivers
- Controlled slew rate drivers on RS422 or RS485 ports - no terminators needed for cables shorter than 300m
- High quality removable screw terminals
Specifications
- Ports:
- 2 Asynchronous ports, Tx and Rx signals only. XON/XOFF selectable
- Port parameters:
-
- RS422/RS485: 0-115200 baud, all character formats
- 20mA: 30-19200 baud
- Interface options:
-
- Standard product: port 1 is RS232; port 2 is RS422/485
- Any combination of RS232, RS422/485 or 20mA loop can be supplied
- RS232:
- Receiver threshold +1.5V typ. Receiver Rin 5kΩ typ. TX o/p ±8V typ (3k load)
- RS422/485:
- Receiver threshold 200mV typ (differential). Receiver Rin 12kΩ min. TX o/p 0 to +5V (no DC load); +2 to +3V (120Ω ohm load)
- 20mA loop:
- Input: LED, nominal drop 2V Output: o/coll. transistor, Vce(sat) < 2V 20mA current source: accuracy ±20%; no-load voltage approximately equal to KD485 supply voltage + 4V
- Power supply:
- 7 - 35VDC (7-26VDC 20mA version)
- Isolation:
- 64V PK, tested at >1000V AC RMS, 1 second
- Environmental:
- Operating temperature 0 to +50°C. Storage temperature -25C to +70C. Relative humidity (operating and storage) 0 to 90%, non-condensing
- Ventilation:
- Rail-mounted KD485 must have a 50mm gap above and below
- EMC complianc:
- Emissions EN50081-2 (94), immunity EN50082-2 (95)
- Dimensions:
- 29mm (W) x 113mm (H) x 100mm (L) approx. in rail-mounted position, including screw terminals