Introduction RS-485 Active Hub
The I-7520U4 is isolated RS-232 to 4-ch RS485 active star wiring hub, which has 4 independent RS-485 output channels and one RS-232 input channel. Each output channel is equipped with an individual driver. The data from a master to the input channel will simultaneously be forwarded to all the four output channels.
Baud Rate Setting
The I-7520U4 provides 2 modes of baud rate setting, one is Self-Tuner mode and the other is fixed baud rate mode. The Self-Tuner mode can support Multiple Baud Rate and Multiple Data Format. The Fixed baud rate mode offers a better quality for data transmission over long or lossy lines or electrically noisy environments.
RS-485 Short-circuit
The Short-circuit protection can automatically shut off the breakdown channel, this kind of design can suffice to protect the communication system. When connected RS-485 equipment breaks down, the breakdown channel will be isolated to ensure that other equipments work normally.
Termination Resistors
In some critical environments, you may need to add termination resistors to prevent the reflection of serial signals. The I-7520U4 includes a 120Ω termination resistor for each channel by jumper selectable.
LED Indicators
The I-7520U4 has 6 LED to indicate the power status and network traffic. The TxD/RxD LED will flash when the unit is being sent out or received data.
Specifications
| Interface | |
| Input | 1 RS-232 Channel: TxD, RxD, GND |
| Output(Slave) | 4 Rs-485 Channels: Data+, Data- |
| 2-wire Cabling | Belden 8941 (2P twisted-pair cable), if different cables are used, the transmission distance may change |
| Transfer Distance MAX Devices Supported |
MAX 1200m at 9.6 kbps; Max 400m at 115.2 kbps 256 (Each Channel) |
| Self-Tuner Asic Inside | Yes |
| Speed | 300~115200 bps via Self-Tuner mode; 1200 ~ 115200 bps via Fixed Baud Rate mode |
| ESD Protection | Yes |
| 2500 VDC isolation on RS-232 | Yes |
| Connection | Removable 10-Pin Terminal Block x 1; 9-Pin Female D-Sub x 1 |
| LED Indicators | |
| Power/Communication | Yes |
| Power | |
| Input Voltage Range | +10 VDC ~ +30VDC (Non-isolated) |
| Power Consumption | 1.2W |
| Casing | Plastic |
| Flammability | Fire Retardant Materials (UL94-V0 Level) |
| Dimmensions (WxHxD) | 72mm X 118mm X 35mm |
| Installation | DIN-Rail |
| Environment | |
| Operating Temperature | -25 oC ~ +75 oC |
| Storange Temperature | -30 oC ~ +80 oC |
| Humidity | 10 ~ 90% RH, non-condensing |
Dimensions (mm)
Pin Assignments
| Terminal No. | Pin Assignment | Pin Assignment | Terminal No. | Pin Assignment | ||||
| RS-485 | 01 | D1+ | CH1 | |||||
| 02 | D1- | |||||||
| 03 | D2+ | CH2 | ISO.GND | 05 | – | |||
| 09 | ||||||||
| 04 | D2- | – | 04 | – | ||||
| 08 | ||||||||
| 05 | D3+ | CH3 | RxD | 03 | – | |||
| 07 | ||||||||
| 06 | D3- | TxD | 02 | – | ||||
| 06 | ||||||||
| 07 | D4+ | CH4 | – | 01 | ||||
| 08 | D4- | |||||||
| 09 | (R)+Vs | RS-232: Female DB-9 Connector | ||||||
| 10 | (B)GND | |||||||