Weidmüller PV DC COMBINER BOX, Operating Instructions Manual

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25 4000001903/00/04.2020
Connection of the communications (optional)
6.3 Configuration of the Modbus address
and the RS485 serial settings
The Modbus device address and the RS485 serial settings
are configured by setting the DIP switches SW1 and SW2.
1
ON ON SW2 SW1
PWR/RS485
DL1
DL2
ALARM
2 3 4 5 6 7 8 1 2 3 4 5 6 7 8
Figure 6.4 Default DIP switch settings on Transclinic 16i+
– All the devices belonging to one RS485 bus
must have the same serial settings.
– The Modbus device address of each Trans-
clinic can only be used once.
– After modifying any DIP switch setting, the
changes need to be applied by powering off
and then back on the equipment.
– Regardless of the SW 2.3 parity bit setting
there is always ONE stop bit.
Description of SW1 (Modbus device address)
The factory default slave address is 1, as shown in the
figure above (i.e. SW 1.1 in the ON position and SW 1.2 to
SW 1.8 in the OFF position). The following table specifies
the binary coding of the Modbus device address via DIP
switches. As an example, the DIP switch coding for Mod-
bus address 175 is shown (10101111 in binary).
SW
1.1
SW
1.2
SW
1.3
SW
1.4
SW
1.5
SW
1.6
SW
1.7
SW
1.8
Weight 2
0
(LSB)
2
1
2
2
2
3
2
4
2
5
2
6
2
7
(MSB)
Address
Increment
1 2 4 8 16 32 64 128
Example
Address: 175
ON ON ON ON OFF ON OFF ON
Description of SW2 (RS485 serial settings)
SW 2.1 SW 2.2 SW 2.3 SW 2.4 ... 2.8
Data signaling
rate
ID number Parity bit
Reserved for
future use
ON
9600 bps
must be left in
default position
EVEN (default) –
OFF
19200 bps
(default)
NONE
must be left in
OFF position
Changing the configuration
To validate the change ID number, baud-rate or parity the
process must be as it follows:
► Switch off the device first.
► Configure the desired ID, baud rate or parity by using
the DIP switches.
► Set the SW2.2 in ON position.
► Switch-on the device.
► Change the SW2.2 from ON to OFF.
► Switch-off the device and wait 5 seconds (any LED
might be ON).
► Switch-on again the device.
6.4 Recommendations when using serial
converters
Transclinic string monitoring devices have been designed
to operate in PV utility scale and PV rooftop industrial-com-
mercial systems. In this type of installation sites, the Mod-
bus RTU client(s) sending requests to the Transclinic is/are
normally:
– A set of PLCs (typically one PLC per inverter shelter)
acting as local dataloggers. In this case a Scada soft-
ware will send Modbus requests to the PLCs instead of
to the Transclinic
– A Scada software located in the control room sends
Modbus requests directly to the Transclinic. In this
case the appropriate RS485 masters for the field buses
should be used, such as Weidmüller Serial/Ethernet
converters, installed in the inverter shelters.
ATTENTION
The RS485 transceiver ICs can be destroyed!
Some Serial/Ethernet converters internally tie the RS485
pin C to their power supply GND. Failure to observe this
particularity could permanently destroy the RS485 trans-
ceiver ICs.
► Please ensure that there are no ground loops (i.e.
different paths to protective earth) in the pin C of the
RS485 bus.
Weidmüller provides also equipment for PV Communica-
tion boxes that can be used to guarantee the best perfor-
mance and compatibility of all the electronic equipment in
the PV site.
Please contact your Weidmüller sales representative for
further information.