User Manual

7000 Bus Converter User’s Manual (Version 1.8 Jan/2006, 7PH-006-18) --------------- 67
o7xxx=module address 01, baud rate=9600
p7xxx=module address 01, baud rate=115200
These three modules can share the same RS-485 network, generated
by s7520.
(4) Therefore there is
256*8=2048 modules max. In one RS-485 network
with a repeater (7510).
The “search function” given in DCON_DOS can search for all these
2048 modules in one RS-485 network. Refer to “DCON_DOS.pdf” for
completely source listing of “search function”.
When the RS-485 network is
over 4000 ft or 1.2Km, the RS-485
repeater (7510) must be added to extend the RS-485 network. For
example, if the qRS-485 is over 4000 ft or 1.2 Km, the t7510 must be
added to extend qRS-485 to rRS-485. And if the rRS-485 is too long,
the user should use another 7510 to extend another RS-485 network. This
is the second function of 7510.
The
power ground of the 7000 series is common ground to the RS-
485 network. This feature is the same as the Adam 4000, Nudam 6000
and DATAFORTH 9B series.
Therefore all the modules in the same RS-
485 network are common ground. For example, the all modules between
n7xxx and o7xxx share the same qRS-485 network and all are common
ground. The qRS-485 length can be up to 4000 ft or 1.2 km, this is a very
long path. This long path makes the RS-485 network
very susceptible to
network noise by high energy transient in this environment. If this noise is
too great, all the modules in the RS-485 network may be
damaged
simultaneously. This is highly possible and occurs often in real world
applications. It is strongly recommended to add another isolation repeater,
the 7510, to break the long path RS-485 network into several short RS-
485 networks to avoid all the modules being damaged at the same time.
This is the third function of 7510.