| Manufacture | ABB |
| Item No | 23WT21 |
| Article number | GSNE002500R5101 |
| Series | Procontrol |
| Origin | Sweden |
| Dimension | 198*261*20(mm) |
| Weight | 0.5kg |
| Customs Tariff Number | 85389091 |
| Type | Modem |
The 23WT21 modem is based on the CCITT V.23 standard, a well-known modulation scheme designed for data transmission over voice-grade telephone lines. The V.23 standard uses frequency shift keying (FSK) to enable reliable data transmission even over long-distance analog telephone connections. It supports data rates of 1200 bps in the downstream receive direction and 75 bps in the upstream transmit direction. It supports half-duplex communication, where data can be transmitted in one direction at a time, from a remote unit to a central station or vice versa. This is common in telemetry or SCADA applications, where devices periodically send data or status information to a central system. The 23WT21 modem is designed to interface with various types of RTUs or PLCs to provide communication capabilities over analog telephone lines. It can be integrated with ABB control systems and other industrial automation equipment, and is compatible with devices that require reliable serial communications.Frequently asked questions about the product are as follows: -What communication protocol does the ABB 23WT21 modem use? The ABB 23WT21 modem uses the CCITT V.23 standard, which uses frequency shift keying (FSK) to communicate over analog telephone lines. -What data transmission speeds does the ABB 23WT21 modem support? The modem supports 1200 bps downstream receive data and 75 bps upstream transmit data, which are typical speeds for half-duplex communication. -How do I connect the ABB 23WT21 modem to a telephone line? The modem connects to a standard analog telephone line (POTS). Simply connect the modem's telephone jack to the telephone line, making sure the line is clear of interference.