The REG system devices require a 12 Vdc power supply and a BUS connection, therefore a total of 4 wires. The REG bus uses the EIA-485 standard (formerly known as RS-485), so the first choice is to use cables specifically created for this type of bus.
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BELDEN, 9841 (see https://www.belden.com/products/Cable/Electronic-Wire-Cable/RS-485-Cable)
CEAM, CPR 6003
TASKER, C521
FANTON, ACS 9841
Note
These models are given as examples of cables that have the suitable electrical characteristics; the electrical designer will have to verify the compliance of the chosen cable with the specific needs of the system: type of installation, fire resistance, etc.; BELDEN in particular has a whole family of EIA-485 cables, suitable for any type of installation).
The use of this type of cable and compliance with the "IN-OUT" wiring is MANDATORY as shown in the following image:
PHOTO TBD
Furthermore, it is important to underline that:
the devices order (REG-DIN-8/REG-EXP-8/REG-TH etc.) is NOT important, they must not be connected in any particular order
each device must be addressed and there cannot be two components with the same address
if the address is changed using a dip switch to any of the components, the power supply must be switch OFF and then ON again for the new address to be acquired
being the MASTER, REG-DIN-8 has no address
the 12 Vdc power cable and the bus cable (A and B) must NOT share the electrical conduits with the 230 Vac
Attention
if a cable is actually used as indicated, the shielding (in the following drawing highlighted in blue) must be connected ONLY IN ONE POINT to the zero of the power supply and where the cable is interrupted, to allow the connection of the various devices (in the example below a REG-DIN-8, a REG-EXP-8, a REG-THL sensor and a REG-OTG), the shielding must be spliced, but NOT connected to anything:
PHOTO TBD
The BUS cable that connects the devices (master, I/O expansions, combined temperature and humidity sensors, displays) as mentioned before MUST be wired "in/out"; do not create backbones or star connections:
PHOTO TBD
if the installation needs do not allow for in-out wiring (houses on several floors for example) it is possible to install signal repeaters/splitters (code RIP-RS485) which allow the bus to be split correctly:
PHOTO TBD
The BUS cable must NOT be closed in a loop, it must ALWAYS be OPEN!
PHOTO TBD
some very large systems may require multiple power supplies, in these cases the references (zero) of all the 12 Vdc power supplies of the regulation system must be short-circuited:
PHOTO TBD
Note
The choice to have multiple power supplies may depend on:
by the fact that there are so many components of the system that a single power supply could not support them all
dal fatto che i componenti (pure non essendo molti) sono molto distanti e quindi la caduta di tensione lungo la linea è tale per cui bisogna mettere un secondo alimentatore all’altro capo
da entrambe le precedenti situazioni
Per quanto riguarda invece le dimensioni dei cavi per l’alimentazione:
Il dimensionamento dipende da come i vari elementi sono distribuiti lungo il bus, e quindi linee guida generali sono impossibili da dareby the fact that the components (even though they are not many) are very distant and therefore the voltage drop along the line is such that it is necessary to put a second power supply at the other end
from both previous situations
As regards the dimensions of the power cables:
The sizing depends on how the various elements are distributed along the bus, and therefore it is impossible to give general guidelines
Infatti il problema non è la capacità dell’alimentatore, quasi sempre sovrabbondante, ma la caduta di tensione lungo la linea
Assumere il caso peggiore (tipo che tutta la corrente, 5A per il PS60 ad esempio, sia assorbita alla fine della linea, diciamo anche solo 30 metri) porta a situazioni irrealistiche, con cavi con sezioni assurdamente grandi
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Se la comunicazione viene ripristinata la spia Err Bus sparisce se si preme il tasto Reset da RegConfig (Pagina Configurazione 1) oppure da display REG tenere premuto il tasto OK all’interno del menu Informazioni – Allarmi/Err.Bus – Errore Bus indir finché l’errore non torna a zero. In alternativa togliere e ridare corrente al REG-DIN-8.
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