Mianyang Weibo Electronic DJS5179 User manual

Instruction Manual of
Technology consultation: 0816-2280829
Quality compliant: 0816-2278273
Sales tel: [phone]
Sales fax: [phone]
Executive standard: GB/T29318-2012
Address: No.98 Youxian East, Youxian District, Mianyang, Sichuan,
China
Code no.: 621000
E-mail: [email protected]
http://www.wbsensor.com
DJS5179 Electronic DC Energy Meter

DJS5179
Preface
Thank you for choosing DJS5179 Electronic DC Energy Meter. We hope that
this product can bring you a pleasant application experience.
If the package or product appearance is damaged when you receive the product,
please contact us or your supplier immediately.
In order to make this product work better and avoid unnecessary troubles caused
by inappropriate operation, please read this instruction manual carefully before
installing, using or maintaining the product.
Please keep this manual carefully for your future use.
Please read the safety instructions in the first section of this manual before
installing this product.
Please note that the content is subject to change without notice.

DJS5179
Catalogue
1.Safety usage instructions ....................................................................................................... 1
2. Product introduction ............................................................................................................. 2
2.1Summary ........................................................................................................................................... 2
2.2Product features ................................................................................................................................ 2
3 Structural features and operating principle ........................................................................ 3
4 Key technical parameters ...................................................................................................... 3
4.1 Key technical parameters ................................................................................................................ 3
4.2 Pulse Output ..................................................................................................................................... 4
5 Outline dimension .................................................................................................................. 4
6 Installation and usage ............................................................................................................ 5
6.1 Installation method .......................................................................................................................... 5
6.2 Installation precautions ................................................................................................................... 5
6.3 Wiring ............................................................................................................................................... 5
6.3.1 Terminals definition .............................................................................................................. 5
6.3.2 Power supply wiring ............................................................................................................. 7
6.3.3 Communication wiring ......................................................................................................... 7
6.3.4 Input wiring ........................................................................................................................... 7
6.3.5 Energy pulse output wiring .................................................................................................. 8
6.4 Usage ................................................................................................................................................. 9
6.4.1Panel description .................................................................................................................... 9
6.4.2 Button description ................................................................................................................ 9
6.5 Display .............................................................................................................................................. 9
6.5.1LCD backlight function ......................................................................................................... 9
6.5.2 LCD display description ..................................................................................................... 10
6.5.3 LCD display content ........................................................................................................... 10
7. Communication protocol .................................................................................................... 1 3 
7.1 MODBUS-RTU protocol ............................................................................................................... 14
7.1.1Summary .............................................................................................................................. 14
7.1.2 Function code description .................................................................................................. 15
7.1.3 Abnormal response ............................................................................................................. 16
7.1.4 Example of Communication Messages .............................................................................. 17
7.1.5 Parameter Register Table ................................................................................................... 19
7.2 DL/T645-2007 protocol.................................................................................................................. 31
7.2.1Summary .............................................................................................................................. 31
7.2.2 Frame format ...................................................................................................................... 32
7.2.3Data identification ............................................................................................................... 33
7.2.4Communication packet description.................................................................................... 39
8 Note ........................................................................................................................................ 45

DJS5169
9 After sales service ................................................................................................................. 45
9.1 New product quality assurance..................................................................................................... 45
9.2 Product warranty limit .................................................................................................................. 45
10 Package, transportation and storage ................................................................................ 46
10.1 Storage .......................................................................................................................................... 46
10.2 Transportation and storage ......................................................................................................... 46
Complimentary clause ............................................................................................................ 46

DJS5179
1
1.Safety usage instructions
This instruction manual is used to describe DJS5169 DC Energy Meter. Please read this
instruction manual carefully before installing, operating and maintaining this product. You are
supposed to have basic knowledge in electrical engineering area by this instruction manual.
The input terminals of this product may carry dangerous voltage during installation and usage,
so the input signal and power must be cut off before any internal or external operation of this
product.
The following special information may appear on this manual or on the product to alert you to
potential hazards or to remind you of safe operation. Any installation and maintenance work must
be performed by a professional.
Danger
Indicating potential dangerous situations which may cause death or serious injury if it is
not obeyed.
Warning
Indicating potential dangerous situations which may cause damage to the equipment if it is
not obeyed.
Attention
Providing other helpful information which is not mentioned in Danger and Warning.
Attention
● The product is an integrated structure, and the internal components are matched and
calibrated;
● Do not damage or modify the label or logo of the product, do not disassemble or
modify the product;
● This product cannot be recycled when it is discarded. Please contact a qualified
recycling department for disposal.
Warning
This instruction is not intended for use as an operational reference by untrained personnel.
The company will try its best to solve the problems caused by the outside of its normal use,
but does not assume the relevant safety responsibility.

DJS5179
2. Product introduction
2.1Summary
DJS5179 Electronic DC Energy Meter is a new generation of programmable intelligent
instrument. The instrument supports DC signal monitoring of two channels voltage and two
channels current. It can be widely applied to DC signal equipment such as DC charging pile and DC
power supply. Equipped with one channel RS485 communication interface, this instrument supports
MODBUS-RTU and DL/T645-2007 communication protocol.
DJS5169 Electronic DC Energy Meter complies with the following standards:
GB/T 29318—2012 “Electric vehicle non-vehicle charger energy metering”;
JJG 842-1993 "DC electronic energy meter";
DL/T 645—2007 “Multi-function energy meter communication protocol”;
MODBUS-RTU communication protocol.
2.2Product features
As an advanced intelligent and digital power grid front-end acquisition component, the DC
Energy Meter mainly monitors the voltage, current, power, and electronic energy in the electrical
circuit in real time. The instrument integrates multi-circuit measurement, display, and
communication. The advantages of this instrument are high measurement accuracy, wide measuring
range, good stability, long-term work free adjustment, programmable parameter setting, etc. The
product follows the development trend of digital, modular, and networked DIN-rail digital display
meters. It is cost-effective and the function combination is simple and practical.
● Full parameter measurement and multiple energy accumulation;
●The input signals between the roads achieve electrical safety isolation;
● Strict EMC and safety protection design and higher reliability;
● High input impedance voltage sampling scheme (≥3MΩ), which has little effect on the
measured line;
● Fast response, data update time (<100ms) and real-time monitoring of grid load changes;

DJS5179
3
● 2 channel electric energy pulse output, 1 channel second pulse output.
3 Structural features and operating principle
The structure of the instrument adopts modular structure design and optional auxiliary power
functions. The instrument adopts guide rail structure design, which is suitable for NS35/7.5,
NS35/15 or European EN50022 standard guide rails. It is easy to install and has strong versatility.
The MCU samples the input signal in real time, performs data processing on the sampling
result and displays it, and communicates with the host computer through the RS485 interface to
realize networking.
4 Key technical parameters
4.1 Key technical parameters
The key technical parameters of this instrument are shown in Table 1.
Table 1 Key Technical Parameters
Technical parameters Parameters
Accuracy
class
Voltage Class 0.2
Current Class 0.2
Energy Class 0.5
Input
Measurement signal 2 channels DC voltage and 2 channels DC current
Voltage
Input scope DC 0～1000V
Linear measurement
range
10%Un～120%Un（Un is rated voltage）
Power consumption < 0.5W
Current
Input scope
DC shunt input current: (Chosen by customer)
100A-500A
DC shunt output voltage: 75mV
Linear measurement
range
1%In～120%In（In is rated current）
Power consumption < 0.1W
Display Displaying method LCD displaying
Power
supply
Voltage scope DC +12V /+24V
Power consumption ≤2W

DJS5179
Ambient
temperature
Operating temperature -25℃～+55℃
Limit operating temperature -40℃～+70℃
Storage temperature -40℃～+70℃
Relative humidity 5%~95%, no condensation and corrosive gases
4.2 Pulse Output
The instrument has 2 channel electric energy pulse output and 1 channel second pulse output,
and the output mode is the open collector optocoupler output. The open collector voltage is VCC ≤
30V, the current IZ ≤ 20mA, and the pulse width should meet the requirements of 80ms ± 20ms.
5 Outline dimension
The outline dimension of this instrument is shown in Figure 1. Unit: mm, tolerance: ±0.5mm.
Figure1 Outline dimension

DJS5179
5
6 Installation and usage
6.1 Installation method
The instrument is lead rail mounted and the width of the lead rail is 35mm.
6.2 Installation precautions
● The product shall be installed in a dry, well ventilated place away from heat and strong
electricity (magnetic) fields.
● Working ambient temperature: -25℃ ～+55℃, humidity: 5%~95% (without condensation).
● It must be installed securely in order to prevent safety accidents caused by vibration.
●Sufficient space shall be reserved around the installation location considering the convenience
and safety for installation and maintenance operations.
● Due to the convenience and safety of installation and maintenance operations, sufficient
space should be left around the installation location of the instrument;
● Electrical connection line requirements: 1.5m2 shielded twisted pair cable is recommended
for the DC shunt mV signal output connection line. The distance between the shunt and the
instrument should not be too long. It is recommended that the line length be within 1m. The
voltage input line and power line should be 1.5mm2 multi-strand flame-retardant copper wire;
1.0mm2 shielded twisted pair cable for RS485 communication;
● Electrical connection requirements: It is recommended to connect a suitable fuse (such as 1A
fuse) to the instrument voltage input circuit.
6.3 Wiring
6.3.1 Terminals definition
Wiring terminals diagram of this instrument is shown in Figure 2 and wiring terminals
definition is shown in Table 2.

DJS5179
Figure 2 Outline of the instrument
Table 2 Wiring terminals definition
Function code Description
+E Power supply positive terminal
GND Power supply ground terminal
RSA RS485communication interface terminal A
RSB RS485communication interface terminal B
U1+ Positive voltage output of Circuit 1
U1- Negative voltage output of Circuit 1
I1+ mV Positive current input of Circuit 1
I1- mV Negative current input of Circuit 1
U2+ Positive voltage output of Circuit 2

DJS5179
7
U2- Negative voltage output of Circuit 2
I2+ mV Positive current input of Circuit 2
I2- mV Negative current input of Circuit 2
P1+ Positive pulse output of Circuit 1
P1- Negative pulse output of Circuit 1
P2+ Positive pulse output of Circuit 2
P2- Negative pulse output of Circuit 2
S+ Positive second pulse output
S- Negative second pulse output
NC Unused.
6.3.2 Power supply wiring
Figure 3 Power supply wiring
6.3.3 Communication wiring
Figure 4 Communication wiring
Attention
Twisted pair cables are recommended.
If a low-quality cable is used, the bus will have high contact resistance or other unfavorable
factors, and the maximum length of the communication bus wiring may not be reached. Lowering
the baud rate may solve the problem.
6.3.4 Input wiring
Warning
In any case, please ensure that the
power supply provided is suitable for
this series of products to prevent
product damage.
Attention:
The terminal must use a
matching resistor (eg 120
Ohms) that matches the
cable's characteristic
impedance
Attention:
For the case of working in severe electromagnetic
interference conditions and transmission at high
transmission rates, we recommend to use the "breaking
terminal method". For example, the matching resistor is
broken into two parts of 2*60 Ohms by means of a
(10-100nF) capacitor that grounds the center tap.

DJS5179
Shunt negative input(X=1,2)
Figure 5 Input signals wiring
Warning
● The rated input voltage shall not be higher than the rated input voltage of the
equipment; terminal block is recommended in consideration of maintenance and 1A
fuse is recommended in the voltage input terminal of the instrument;
Attention
● The shunt should be connected to negative pole;
● The wiring method on site must be consistent with the product configuration and the
input voltage and current are in the same direction as the wiring diagram. Otherwise,
the equipment may not function properly or even be damaged.
6.3.5 Energy pulse output wiring
Figure 6 Energy pulse output wiring
Pulse detection device
IZ
EP-
EP+
VCC
R
Pulse detection port
Attention
The pulse output is the open
output of the optocoupler
collector. Please ensure
VCC≤48V and IZ≤12mA during
use to prevent damage to the
pulse output port of the product.

DJS5179
9
6.4 Usage
6.4.1Panel description
Displaying panel is seen in Figure 7. Displaying panel description is seen in Table 3.
Figure 7 Displaying panel
Table 3 Displaying panel description
Identification Description
RUN Product operating indicator light
RXD Communication receiving indicator light
TXD Communication sending indicator light
EP1 Electronic energy pulse output indicator light of circuit 1
EP2 Electronic energy pulse output indicator light of circuit 2
Button
6.4.2 Button description
Button : Used switch the order of the display content of the instrument.
6.5 Display
6.5.1LCD backlight function
The LCD backlight turns on when the button is pressed and turns off automatically after 15
seconds.

6.5.2 LC
D
LCD
Item
Full scr
e
Indicati
n
symbo
l
6.5.3 LC
D
Ther
e
Different
d
No.
1
2
6.5.3.1 Au
Whe
n
screen aft
e
set), it. T
h
default are
D
displa
y
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e
display des
e
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l
s
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displa
y
c
o
e
are two
t
d
isplay met
h
A
u
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e
tomation
c
n
the backl
i
e
r running
f
h
e display s
as follows
:
e
scription
cription is
s
Di
s
o
ntent
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ypes of L
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ods and c
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tomation cy
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cle displ
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ght is off,
f
or a certai
n
equence a
n
:
s
een in Fig
u
Figur
s
play content
C
D displa
y
o
rrespondin
g
Figure 5
D
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m
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a
y
ay
the produc
n
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f
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o
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re 4.
e 4 Display
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isplay cases
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ethod
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f
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c
o
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ontent
F
c
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D
I
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m
atic cycle
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ription are
description
W
h
W
h
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ged autom
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c
onds in d
e
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c
F
ull screen di
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ircuit 2
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ata in high l
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ata in low l
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B
eing on the
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en the
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en the back
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tically to
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e
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ure 5.
D
escription
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ight is on
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5
to 20 sec
o
b
e set. Th
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indicate
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No.
on the
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1
2
3
4
5
6
7
8
LCD d
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splay conten
Figur
t
V
(
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C
(
A
P
(
k
P
e
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e
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(
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A
P
(
k
DJS51
e 6 Display
c
Display it
e
name(Un
V
oltage in ci
r
V
)
C
urrent in ci
r
A
)
P
ower in ci
r
k
Wh)
P
ositive
e
e
nergy in ci
r
k
Wh)
N
egative
e
e
nergy in ci
r
k
Wh)
V
oltage in ci
r
V
)
C
urrent in ci
r
A
)
P
ower in ci
r
k
Wh)
79
c
ontent
e
m
it)
r
cuit 1 Vo
l
10
0
r
cuit 1 Cu
r
r
cuit 1 Po
w
30
0
e
lectric
r
cuit 1
Pos
cir
c
Dat
lo
w
cyc
l
e
lectric
r
cuit 1
Ne
g
in c
Dat
lo
w
cyc
l
r
cuit 2 Vo
l
10
0
r
cuit 2 Cu
r
r
cuit 2 Po
w
30
0
Descript
i
l
tage in c
0
0V
r
rent in circu
i
w
er in c
i
0
kWh
itive electric
c
uit 1: 36kW
h
as both in
w
er levels are
l
e automatic
a
g
ative electr
i
ircuit 1:0kW
h
as both in
w
er levels are
l
e automatic
a
l
tage in c
0
0V
r
rent in circu
i
w
er in c
i
0
kWh
i
on
ircuit 1:
i
t 1: 300A
i
rcuit 1:
energy in
h
;
high and
displayed
a
lly
8
h
4
l
b
d
i
c energy
h
;
high and
displayed
a
lly
8
h
4
l
b
d
ircuit 2:
i
t 2: 300A
i
rcuit 2:
11
Note
8
bites i
n
h
igh level
4
bites i
n
l
ow level +
4
b
ites
d
ecimals
8
bites i
n
h
igh level
4
bites i
n
l
ow level +
4
b
ites
d
ecimals
n
n
4
n
n
4

9
10
11
12
13
14
15
P
e
(
k
N
e
(
k
M
6
c
a
6
c
a
R
c
R
c
DJS51
P
ositive
e
e
nergy in ci
r
k
Wh)
N
egative
e
e
nergy in ci
r
k
Wh)
M
odbus
communicat
i
address
6
45
M
c
ommunicati
o
a
ddress in cir
c
6
45
M
c
ommunicati
o
a
ddress in cir
c
R
ated inp
u
c
ircuit 1 (V/
A
R
ated inp
u
c
ircuit 2 (V/
A
79
e
lectric
r
cuit 2
Pos
cir
c
Dat
lo
w
cyc
l
e
lectric
r
cuit 2
Ne
g
in c
Dat
lo
w
cyc
l
i
on Mo
d
add
M
odbus
o
n
c
uit 1
645
co
m
cir
c
Dat
lo
w
cyc
l
M
odbus
o
n
c
uit 2
645
co
m
cir
c
Dat
lo
w
cyc
l
u
t in
A
)
Rat
e
10
0
u
t in
A
)
Rat
e
10
0
itive electric
c
uit 2: 36kW
h
as both in
w
er levels are
l
e automatic
a
g
ative electr
i
ircuit 2:0kW
h
as both in
w
er levels are
l
e automatic
a
d
bus com
m
ress: 1
m
munication
a
c
uit 1: 1;
as both in
w
er levels are
l
e automatic
a
m
munication
a
c
uit 2: 1;
as both in
w
er levels are
l
e automatic
a
e
d input in
0
0V/300A
e
d input in
0
0V/300A
energy in
h
;
high and
displayed
a
lly
8
h
4
l
b
d
i
c energy
h
;
high and
displayed
a
lly
8
h
4
l
b
d
m
unication
Modbus
a
ddress in
high and
displayed
a
lly
4
h
8
l
Modbus
a
ddress in
high and
displayed
a
lly
4
h
8
l
circuit 1:
circuit 2:
8
bites i
n
h
igh level
4
bites i
n
l
ow level +
4
b
ites
d
ecimals
8
bites i
n
h
igh level
4
bites i
n
l
ow level +
4
b
ites
d
ecimals
4
bites i
n
h
igh level
8
bites i
n
l
ow level
4
bites i
n
h
igh level
8
bites i
n
l
ow level
n
n
4
n
n
4
n
n
n
n

16
17
18
19
20
21
6.5.3.2 Bu
The
m
the numbe
r
7. Com
m
DJS5
interface.
messages
c
simultane
o
The
c
wire diam
e
kept away
tton c
y
cle
d
m
eter is pre
r
of displa
y
m
unicati
o
179 Electr
o
2 protoco
l
c
an be tra
n
o
usly on on
e
c
ommunica
t
e
ter of not
from stron
g
d
ispla
y
ssed by th
e
y
screens ca
n
o
n proto
c
o
nic DC
E
l
s as MO
D
n
smitted on
e
line, and
e
t
ion conne
c
less than 1
g
electrical
B
v
d
、
P
c
P
c
D
d
T
s
L
e
user to s
w
n
be set. Se
t
c
ol
E
nergy Me
t
D
BUS-RT
U
the comm
u
e
ach meter
c
c
tion shoul
d
.0 mm2.
W
cables or o
t
DJS51
B
aud rat
e
v
erification
m
d
ata bite (bit)
stop bite（
b
P
ulse const
a
c
ircuit 1
P
ulse const
a
c
ircuit 2
D
ate(Year
d
ay)
T
ime (Hour
m
econd)
L
CD display
o
screen
w
itch the L
C
t
tings in de
f
t
er provide
s
U
and DL/
T
u
nication l
i
c
an set its
c
d
use a shie
W
hen wirin
g
t
her strong
e
79
e
、
m
ode、
b
it）
Ba
u
Ve
r
ve
Dat
Sto
p
a
nt in Pul
s
1：
a
nt in Pul
s
2：
month Cu
r
20
2
m
inute Cu
r
m
i
o
n full LC
D
sc
r
C
D, and the
f
ault are se
e
s
serial ha
l
T
645-2007
i
ne. Up to
c
ommunica
t
lded twiste
d
g
the lines,
e
lectric fiel
u
d rate: 9600
;
r
ification m
o
rification;
a bite: 8bit;
p
bite: 1bit
s
e constant
50
s
e constant
50
r
rent date:
2
2
r
rent time: 1
4
i
nute 0 secon
D
display
r
een
display or
d
e
n in Figur
e
l
f-duplex
R
are optio
n
64 instrum
e
t
ion addres
s
d
pair with
the comm
u
ds.
;
o
de: even
in circuit
in circuit
July 1st,
4
hours 0
d
on full
d
er of each
e
6.
R
S485 co
m
n
al, and v
a
e
nts can b
e
s
.
a copper
m
u
nication l
i
1
3
screen an
d
m
municatio
n
a
rious dat
a
e
connecte
d
m
esh with
a
i
ne shall b
e
3
d
n
a
d
a
e

DJS5179
7.1 MODBUS-RTU protocol
7.1.1Summary
The MODBUS protocol uses a master-slave response mode of communication connection on a
communication line. First, the signal of the host computer is addressed to a terminal device (slave)
with a unique address, and then the response signal from the terminal device is transmitted to the
host in the opposite direction, i.e., the signal along a separate communication line The opposite
direction transmits all communication data streams (half-duplex mode of operation).
The MODBUS protocol only allows communication between the host (PC, PLC, etc.) and the
terminal device, and does not allow data exchange between independent terminal devices, so that
each terminal device does not occupy the communication line when they initialize, but only
responds the signal arriving to the machine.
Host Computer Query: The query message frame includes the device address, function code,
data information code, and calibration code. The address code indicates the slave device to be
selected; the function code tells the selected slave device which function to perform, for example,
function code 0x03 is to ask the slave device to read the register and return their contents; the data
segment contains the slave device to perform the function. Any additional information, such as in
the read command, the additional information of the data segment has the number of registers from
which to start reading and the number of registers to be read; the check code is used to verify the
correctness of a frame of information, and the slave device provides a verification message content.
Is it the correct method, it uses the calibration rules of CRC16.
Slave response: If the slave generates a normal response, the response message has a slave
address code, a function code, a data message code, and a CRC16 check code. The data information
code includes data collected from the device: such as register values or status. If an error occurs, we
agree that the slave does not respond.
The transmission method refers to a series of independent data structures within a data frame
and limited rules for transmitting data. The following describes the transmission mode compatible

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with the RTU mode of the MODBUS protocol. Each data frame includes 1 start bit, 1 function bit, 8
data bits, (parity bit), 1 stop bit (when there is a check), 2 stop bits (when there is no check). The
structure of the data frame: that is, the message format.
Address code Function code Data code Check code
1 BYTE 1BYTE NBYTES 2BYTES
The address code is composed of one byte (8-bit binary code) at the beginning of the frame,
and the decimal is 0 to 255. In our system, only 1 to 247 are used, and other addresses are reserved.
These bits indicate the address of the user-specified terminal device that will receive the host data
from it. The address of each terminal device must be unique, and only the addressed terminal will
respond to the query containing the address. When the terminal sends back the slave address data in
a response, it tells the host which terminal is communicating with it.
Figure 8 Schematic diagram of query response
7.1.2 Function code description
The function code tells the terminal which terminal is performing what function. The following

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table lists the function codes, their meaning and function supported by the meter.
Code Meaning Action
0x03 Read data register Get one or more register values inside the current meter
0x05 Switching output control Controls a relay inside the current meter
0x10 Set multiple registers Write the specified value to 1 or more registers inside the meter
The data code contains the data required by the terminal to perform a specific function or the
data collected by the terminal in response to the query. The contents of these data may be numeric
values, reference addresses, or set values. For example, the function field code tells the terminal to
read a register, the data field needs to indicate which register to start and how many data to read,
and the slave data code returns the data length and corresponding data.
The Check Code Error Check (CRC) field occupies two bytes and contains a 16-bit binary
value. The CRC value is calculated by the transmitting device and then appended to the data frame.
The receiving device recalculates the CRC value when receiving the data, and then compares it with
the value in the received CRC field. If the two values are not equal, error occurs.
The process of generating a CRC is:
1. Preset a 16-bit register to 0FFFFH (all 1), which is called CRC register.
2. XOR the 8 bits of the first byte in the data frame with the low byte in the CRC register and
store the result in the CRC register.
3. Move the CRC register one bit to the right, fill the highest bit with 0, and the lowest shift out
and detect. If the least significant bit is 0: repeat the third step (next shift); if the lowest bit is 1: the
XOR register is XORed with a preset fixed value (0A001H).
4. Repeat steps 3 and 4 until 8 shifts. This completes a complete eight bit.
5. Repeat steps 2 through 5 to process the next eight bits until all byte processing ends.
6. The value of the final CRC register is the value of the CRC.
7.1.3 Abnormal response
When the meter detects an error other than the CRC check code error, it will send back
information to the host. The highest position of the function code is 1, that is, the function code