Individual Foxtrot modules should be connected with cables intended for the RS-485 bus, the minimum of 2 pairs (for the connection of the communication bus, see Chapter 3.3.3), or with cables that include the power supply. Regarding the TCL2 bus, a cable designed for the RS-485 bus must be used. (For connections including the power supply, see Chapter 3.3.2).
In the case of larger distances (typically over 10m), only the communication bus is always connected, without the power supply (see Chapter 3.3.3). A good quality shielded cable must always be used, and the shield MUST always be connected to the main ground terminal at only one end of the cable!
The TCL2 bus interconnected with metallic cables (RS-485) should always be terminated at both ends. On the side of the basic module there is a firm termination right inside the basic module - the basic module MUST always be at one end of the bus!
The other end of the bus should be terminated with an external resistor with about 120 Ω mounted between the TCL2 + and TCL2- signals. For easy installation there is included in the package of the basic module a KB-0290 terminator (a separate order number TXN 102 90), which contains the required 120 Ω terminating resistor, which is fitted to be inserted into the TCL2 terminals (usually A1, A2). During the assembly, insert the terminator into the terminals, insert also the installed wire for the connection of the bus, and tighten the terminals.
The modules can also be interconnected via fibre-optic cables or a combination of fibre-optic and metallic cables. For fibre-optic cable connection it is necessary to use the KB-0552 optical converter (for the wiring see Chapter 3.3.5). The modules should be connected via standard ST-ST patch cables..
The fibre-optic cable provides galvanic isolation and therefore an independent power supply of the next module is necessary.
The table below provides a summary of characteristics of possible ways how to link the Foxtrot modules into assemblies. Naturally, the listed possibilities of linking can be combined:
Tab. 1. Possibilities of linking the Foxtrot modules - a summary
Solution |
1 |
2 |
3 |
HW (additional) |
- |
- |
KB-0552 |
Transmission medium |
Cable (2x twisted pair) |
Twisted pair + GND (2x twisted pair) |
Fibre-optic cable |
|
|
|
|
Distribution of power supply |
YES |
NO |
NO |
Galvanic isolation of the bus |
NO |
NO |
YES |
The cable used |
According to specification |
According to specification |
Standard patch cable ST-ST |
Connector |
Screw terminals |
Screw terminals |
2x ST |
Attenuation (about) |
- |
- |
3.5 dB/km |
Wavelength |
- |
- |
820 nm |
The type of fibre |
- |
- |
glass multimode 62.5/125 mm |
Maximum number of I/O modules to one CP |
10 |
10 |
10 |
Maximum length of one bus segment |
10 m |
400 m |
Maximum 1.7 km |
Maximum bus total length |
10 m |
400 m |
According to the number of segments |
For detailed information see |
Notes on the individual solutions:
-
The basic method of interconnection including the power supply. Suitable for assemblies with multiple modules in a single control panel. This solution is limited by a maximum bus length (power supply).
-
This interconnection is suitable for longer distances between modules - the control system is distributed in several panels in technology, etc. Each module (or several modules together) must have its power source. The TCL2 bus connection allows the use of any cable that meets the requirements for the RS-485 bus, and it can run through channels, bushings of control panels.
-
Long-distance connections (the highest quality solution). As the lengths of each segment are added together, the total bus length of the entire system can reach a kilometre. The fibre-optic cable provides galvanic isolation and therefore the module (or a set of modules) connected with an fibre-optic cable must contain power supply.