ICP DAS USA 7000 Series User Manual page 21

Note: the power ground of
and RS-485 is
ground.
This is the same for
Adam 4000, Nudam 6000 and
DATAFORTH 9B series modules.
In most applications, the
RS-485 network. Normally the
ground as the
Therefore the
if there is any high voltage transient on
will be free from damage.
WARNING!! ERROR CONDITION 1: if the
the 7520R uses the same DC power ground with
The Host PC/PLC is common ground with
(1)
The RS-232 is common ground with power ground of
(2)
The power ground of
(3)
7000
The power ground of
(4)
Therefore the
That is to say, there is no isolation between
network. The Host PC/PLC may be damaged if there is high voltage transient
on RS-485 network.
7000 Bus Converter User's Manual (Version 1.8 Jan/2006, 7PH-006-18) --------------- 21
7000
common
7520 are used to convert the
Host PC/PLC, and the isolation site is in the RS-232 section.
Host PC/PLC is isolated from
7520R is common ground with power ground of
7000 is common ground with
Host PC/PLC is common ground with
7520 does not use the same DC power
RS-485 network. That is to say,
RS-485 network, the
7520 are replaced by
Host PC/PLC and
RS-232 signal to
Host PC/PLC
7520R and
7000. In this situation,
RS-232
7520R
RS-485
RS-485 network.
RS-485