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If you are trying to get two ancient pieces of equipment (both of which use true RS-232 drivers and receivers) to work with a long cable, the capacitance limit in RS-232 may apply, but RS-232 does not take bit rate into account. If you are pushing the data rate above 100kbit or the line length above 1000 meters, you may want to use a better grade of wire. If the can't, try reducing the bit rate. Empirically determined means try it and see if it works. But before we dive deep into those SATA cable classifications, we need to have a look at what SATA actually means. It should be noted that RS-422 is limited to 10Mb and devices meeting the RS-422 standard do not need to operate over the full range. The entire subject of handshaking is obsolete with modern USB to RS-485 adapters since the PC's driver's and/or hardware handle driver enabling, and a modern PC can handle data rates much faster than can be transmitted over an RS-485 network. Transmitting data bidirectionally over the same wire(s), rather than unidirectional transmission, requires a turn-around delay. Low data rates are primarily limited by the DC resistance of the cable (the effects of the DC resistance of the cable are made worse if a termination resistor is used) and high data rates are limited by the AC effects of the cable on signal quality.

Often, use of shielded CAT5/6 cable can give an adequate signal ground, although this is not recommended. 0.2 is the minimum recommended voltage difference that receivers use to detect a change in polarity. The driver must produce a differential voltage between 2 and 10V into a loaded/terminated cable. For isolated gadgets, what is rs485 cable the reference voltage can significantly impact communication within an RS-485 network. If you keep the cable length at 70% or 80% of this limit you should expect the network to work with a true RS-232 driver and receiver. In reality either or both the driver or receiver are going to meet the more modern RS-574 requirements and none of the RS-232 limits will apply. The legends and folklore, not to mention the flat out wrong information that has grown around the line length and data rate limits inherent in RS-485 are truly astounding. RS-485 has even less information. RS-485 discusses that it is used for devices up to 10Mbit/S, then says they need not be limited to 10Mbps. It also states that "the upper bound is beyond the scope of this Standard".

2, disadvantages: Precision but for outdoor and harsh environments offer higher protection requirements; measuring linear displacement is dependent on plant transformation, the need to eliminate the error caused by mechanical clearance; detection of objects in orbit is difficult to overcome the slip. It also features embedded circuits protection features such as power isolation, ADI magnetical isolation, and TVS diode. Clueing in from its name, this is a USB to RS485 converter with industrial-grade features. If reducing the bit rate is not an option, then you could try an RS-232 to RS-485 converter at both ends. Try to find the capacitance of the cable being used (in pF/foot) and divide 2500 by it. Can first close switch with ordinary first position, and then find the closest Z-signals (each in the same direction to find), filled with hope when the do not forget its phase modulation and phase grating line, otherwise not allowed.

It is like the Universal Serial Bus (USB) or ethernet that we can find in many of our modern computers. It converts a USB port to use with RS485. This cable provides a USB type A connector for the PC end and an RJ11 connector for the meter end. Normally, this connection is made at one end of the main cable. Another major advantage is that there can be more than one slave in the connection. In reality, if you are using relatively modern equipment (say 1990 or later) and a low baud rate, line lengths of 1,000 feet (300 m) or more are possible. The appendix discusses capacitance and resistance of the cable, then gives an example calculation where the capacitance of the cable per foot (30pF/foot) multiplied by the cable's length, plus the capacitance of the receiver (100pF) gives a maximum cable length of 80 feet. This should give you an approximate limit for that cable in feet.