35
Notice that all the three lightning protection boards have one side marked “
Field
” or “
Line
”,
this is the side where the cable coming from the field should be connected. The other side,
which is marked “
Device
” is the side where the protected device will be connected.
Notice also that the RS485 protection board has at both sides of its terminals one terminal,
which is marked by a white spot and the other which is not. This is done in order to be able not
to confuse between the “P” (positive) and “N” (negative) wires of the RS485, if the “P” was
connected to the white spot terminal on one side the continuation of the “P” at the other side
should also be connected to the white spot.
Although lightning protection units can do a very good job protecting the system from
being severely damaged by lightning, it must be understood that we cannot expect a
100 percent protection in any case. There is no protection against a direct hit; the
energy of the lightning is too high to be absorbed by any protection system.
6.4
The enclosures of the DREAM system
The DREAM 2 controllers can be ordered in one of the two enclosure formats:
PLASTIC ENCLOSURE METAL CABINET
The metal cabinet is meant for wall mounting, it has a bigger size and therefore it may
accommodate additional interfaces, expansion boards, lightning protection boards which
otherwise would be located in additional boxes. The plastic enclosure can be wall mounted or
installed on a metal pole. Any additional equipment that cannot be installed inside the enclosure
will be installed externally in separate boxes.
7.
INSTALLATION STEPS
Setting up a DREAM control system consists of the following steps:
Mounting the controller and its peripherals.
Defining the system’s configuration.
Connecting the input/ output devices to the controller and to the RTUs based on the
connections list resulting from the configuration process.
Testing the operation of all the inputs/ outputs.