There are open design documents of SCH/PCB for these modules (easy to design, no need software setting) Modules are done by the chip PWBS331 and PWBS751. PWBS01H can achieves the function of DC power over RS485 and can work in tree star network topology for RS485 in reliable. DC power line communication.

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RS485 DC POWER TRANSMISSION MODULES
NOTICE
There are open design documents of SCH/PCB
for these modules (easy to design, no need
software setting)
Modules are done by the chip PWBS331 and
PWBS751.
GENERAL DESCRIPTION
With the benefits of PWBS331 chip, this
RS485 POWER transmission module can
provide DC power and transceiver RS485 data
by only two wires. Every terminal can get
0~24W power, totally hundreds watts. If set
the power level well on every terminal, it will
support stable communication for 512 points.
Transparent communication from host to
remote site by RS485 half‐duplex mode, it
also has no packet limit for the data
transceiver. PWBS series modules can support
stable work in more than 10km long distance.
Strong anti‐interference ability [1]
makes
robustness communication result with no
limit on wire type, and supports both of
twisted‐pair cable and parallel wires. PWBS
module solution also permits the network
working through pipes close to 220VAC lines.
Stable work on tree network, star network
and others any network topology. Because of
the unique principle of this technology, it can
pass through the test of surging at 4KV level,
EFT (Electrical Fast Transient) at 2KV level,
conducted interference at class 3 [2]
. PWBS
series module adopts shell with guide rail
which can be easy to assemble on industry
field directly.
[1] Customer can only use the stable
communication function, not use the DC
POWER transmission function.
[2] All the tests mean on the POWER BUS line,
not RS485 interface.
PRODUCT PICTURES
Host module Slave module
KEY FEATURES
Done by the square wave BUS chip
PWBS331
Provides RS485 half‐duplex
communication and DC power on only
two wires.
9600bps (H1 Host module)，2400bps(H2
Host module)
Every terminal supports 0~24 watt（Need
to consider the voltage drop on
wires）.Also can be expended to 2A.
Provide DC power transmission over
ready RS485 network
Provide RS485 transceiver over ready DC
power line
No limit on cable type, also support
parallel wires.
Support tree network, star network and
any other network topology
Support 10km stable work.
Support 512 terminals
Host module permits 960 watt
transmission (H2), or 240 watt (H1)
[2]
Easy to pass through the surging test at
4KV, EFT at 2KV，conducted interference
at Class3

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APPLICATION BLOCK
Supports tree network and start network in long distance
PIN DESCRIPTION
Host module
1. NC
2. NC
3. NC
4. NC
5. NC
6. RS485 interface’s B line
7. RS485 interface’s A line
8. NC
9. NC
10. The target DC transmission power’s GND
11. The target DC transmission power’s
positive input V+
12. PWBS Bus’ output P+ (No polarity)
13. PWBS Bus’ output P‐ (No polarity)

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Remote module
1. PWBS Bus input P+ (No polarity)
2. PWBS Bus input P‐ (No polarity)
3. DC transmission output (not fixed
voltage, 0.5A current ability. Also can be
expended to 2A)
4. Back up terminal
5. 5/12/24V fixed voltage output with low
than 500mA current ability
6. GND
7. RS485 interface’s A line
8. RS485 interface’s B line
PRODUCT SELECTION
Part number Function Ability
PWBS01H1 Host 240 watt DC power transmission ability. 9600bps baud rate(1)
PWBS01H2 Host 960 watt DC power transmission ability. 2400bps baud rate(1)
PWBS‐01S5 Slave 5V/500mA fixed voltage output
PWBS‐01S12 Slave 12V/500mA fixed voltage output
PWBS‐01S24 Slave 24V/500mA fixed voltage output
V1 and V3 can work together to have a dual voltage output(2)
【NOTICE】
(1) Transparent in N, 8, 1 form (also compatible N, 9, 1).Supports 1000 bytes as the maximum
packet size.
(2) If hope to use V1, V3 together, the total current should be control to under 0.5A. If high
current needed, please connect to factory.
ELECTRICAL CHARACTERISTICS (TA = 25°C unless otherwise noted)
Host module PWBS01H1
V+ to GND 17~50V
P+ to GND 17~50V
P+ Pin maximum current 5A
Host module PWBS01H2
V+ to GND 17~50V
P+ to GND 17~50V
P+ Pin maximum current 20A
Slave module PWBS‐01
V+ to GND 12~40V (3)
V1 Pin maximum current 500mA
V3 Pin maximum current 800mA
Temperature range_
‐25~85°C
【NOTICE】
(3) Have to make the slave module’s input voltage high than 12V so that the slave module can
work well (Improve the diameter of the cable to get the target slave voltage when long distance
application). But can’t high than 40V

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APPLICATION GUIDE
General
Please refer Fig.1 to connect host and slave
modules. The two wires Bus has no polarity,
but target transmission DC power and RS485
interface need to be connected in right
polarity.
PWBS series modules support the fixed
voltage output and the non‐fixed output. If
you want to get DC power’s transmission on
fixed output in remote site, please use V1. If
hope to get non‐fixed transmission output,
please use V3 pin. V3 is the natural voltage of
a DC power’s transmission subtracting the
voltage drop on lines. Customer can use our
non‐isolated low cost power module to get
your target output which V1 can’t achieve.
About host module
PWBS series host modules support the data
rate of 9600bps and 2400bps in transparent N,
8, 1 and N, 9, 1 form.
PWBS01H1 host module permits 5A current
output which means the maximum power is
48V*5A=240 watt. PWBS01H1 supports
9600bps data speed.
PWBS01H2 host module permits 20A current
output which means the maximum power is
48V*20A=960 watt. PWBS01H2 supports
2400bps speed only.
In long distance application, because of the
voltage drop on power bus lines, the remote
site can’t get full power of the host module.
If customer hopes to use RS232 or USB
interface to connect with system’s host side,
please use a RS232/RS485 or USB/RS485
adapter connecting to RS485 pins like below
(please connect factory).
About slave modules
Slave module PWBS‐01S_ series support as
big as 500mA load with 5/12/24V voltage
output by V1.
【NOTICE】PWBS‐01S_ series only support
40V input as the maximum rate. If the host
module’s DC transmission voltage is bigger
than 40V, please make sure to calculate the
voltage drop so that the bus voltage to
PWBS‐01S_ is low than 40V
【NOTICE】If hope to use V1, V3 together, the
total current should be control to under 0.8A.

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APPLICATION EXAMPLES
Example 1
On engineering hopes to have RS485
communication over the ready DC voltage
transmission lines, do not need to calculate
the voltage drop, customer can use the
modules directly because the power
consumption of PWBS series is very low
(0.01W) so that there will be no influent on
the factor of voltage drop. For examples, one
industry project used 4 wires to achieve 500m
communication by 2 DC power lines and 2
RS485 lines in the past. For new engineering,
they can use PWBS series modules to omit
RS485 lines. No need calculation for voltage
drop. Fig.1
Example 2
The ready network is RS485. Some of the
remote devices get power from local AC/DC
power. Some of the remote devices get power
from DC lines or battery. PWBS series module
can help to omit the AC/DC power, and DC
lines and battery. Please notice that in that
case, engineer needs to calculate the voltage
drop according to the Fig.4 (Just for reference)
【Notice】
Slave modules needs at least 12V to start a
work, which means the DC transmission
power subtracts the voltage drop should
bigger than 12V.
Example 3
A complicated engineering field which hopes
to adopt tree network or star network,
multi‐type cables lapping, and even target to
pair cables with 220VAC in parallel in pipe, If
PWBS series adopted, all problems the RS485
is facing will be solved well essentially.
Engineer can only use the stable
communication ability, and leave the power
transmission function alone.
Example 4
One project hopes to have 5000m long or
longer distance communication. Just use slave
module adding host module in 2500m point
as a repeater then it can achieve that target.
Please notice that the repeater point needs to
re‐add DC transmission power for the host
module. Fig.2
Example 5 (Low cost way)
If DC transmission function doesn’t be used,
no need to use PWBS series on every of the
engineering terminal. To down the total
system cost, just use PWBS in the network’s
branching which is hard to communication by
RS485. This is typical in network and star
topology like Fig.3
Other examples
All the target engineering on ready DC
transmission lines do not need to calculate
the voltage drop, but other application which
hope to transmit DC power in ready RS485
lines or a new type of DC power lines
engineer needs to consider the voltage drop
carefully especially in below areas.
High power smart LED control/monitor
Long distance communication
Thin wires
[Other solution]
If hope to have high voltage DC transmission than 48V, such as 400V/200VDC or high power
than 40W in single port, or high data rate than 9600bps such as 115200bps, or other
interface such as CAN/Ethernet/HART, please connect factory.

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Fig.1
Fig.2

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Fig.3
Fig.4

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Module size：
Host module（L x W x H）115mm x 90mm x 40mm
Slave module（L x W x H）80mm x 50mm x 30mm (Not including the assembling hole)