SNV Engineering SNV018EC.XX, Руководство пользователя и инструкция по установке

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S N V 0 1 8 E C . X X
U S E R & I N S T A L L A T I O N M A N U A L
V 3 . 1
© SNV Engineering Ltd
9
CAUTION
The card must be installed following the below restrictions:
>= 8mm gap from grounded plates
>= 15mm gap from non-grounded plates
Note: The gap is defined as the distance between relevant plate, or other
element and the card routes, or components’ pins, or the highest component
mounted on the card, including any other conducting element, like bolts, nuts,
bar, cables and cable terminals fixed on the card
Connector CON6 is a dry contact input, having two states depending the contact
of the connector’s two pins or not.
CAUTION
No voltage should be applied to any of the two pins of CON6
SNV018EC card uses RS485 bus for data communication. Cards are connected to
the bus in series using twisted pair cable. Card has two equivalent connectors
(CON1/CON2 and CON3/CON4) to facilitate connection of multiple cards in series.
It is suggested to connect all cards in series in a “line”, preferable with the master
controller in the middle. If not convenient a star topology, with the master
controller in the center, may work depending of the cable length, the number of
the lines, and their relative lengths. In any case all the terminal nodes must be
terminated with the appropriate resistor (see Annex B). Bias resistors also must be
installed (see Annex B).
RS485 transceiver used supports up to 128 nodes; hence up to 127 boards can be
connected to the same bus. The total length of the cable used for the boards
interconnection is suggested not to exceed 1200m, when bus repeaters are not
used.
The same cable can be used for the power supply of the cards, using an extra pair.
The power supply source should be 24Vdc and the current capacity should not
exceed 5A. It is suggested, where the number of cards allow, to use a power
supply of 1A, since the on-board PCB fuse is 1A rated. A clamp diode is installed at
power supply terminals after the on-board PCB fuse. If power supply polarity is
wrong, current will be conducted through the diode, blowing the fuse.