990XCP98000 SQUARE D, 990XCP98000 Datasheet - Page 249

• Manufacturer Part Number: 990XCP98000
• Description: QUANTUM CPU BATTERY FOR S
• Manufacturer: SQUARE D

Specifications of 990XCP98000

• Rohs Compliant: YES
• Battery Capacity: 1800mAh
• Battery Technology: Lithium
• Battery Voltage: 3V
• Battery Terminals: Connector
• Weight: 0.12lb

Performance
Read coils (01)
Read discrete inputs (02)
Read holding register (03)
Read input register (04)
Write single coil (05)
Write single register (06)
Write multiple coils (15)
Write multiple registers (16)
Read file record (20)
Write file record (21)
Mask write registers (22)
Read/write multiple registers (23)
Read device identification (43)
Evaluating the network load
Modbus request/response (function code)
Response
Request
Response
Request
Response
Request
Request
Response
Request
Response
Request
Response
Request
Response
Request
Response
Request
Response
Request
Response
Request
Response
Request
Response
Request
(continued)
(continued)
Total PDU
length
5
2 + N
5
2 + N
5
2 + N
5
2 + N
5
5
5
5
6 + N
5
6 + N
5
9
4 + N
9 + N
9 + N
7
7
10 + M
2 + N
4
Function
code
length
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
Modicon
automation platform
System approach
Ethernet TCP/IP network performance
To evaluate the bandwidth used by the I/O Scanning service, the following parameters
must be defined for each station scanned:
1
2
3
Note: The scanning period is limited by the response time of the scanned peripheral device.
The network load of the I/O Scanning service in bps can be evaluated using the
following formula:
(103 + 2 x size of the read variables + 95 + 2 x size of the write variables)
x
8000/scan time
The calculation must be performed for scanned peripheral devices on each scanning
station.
Evaluating the I/O Scanning service
Scanning period
Size of read variables
Size of write variables
Para-
meter
length
4
1
4
1
4
1
4
1
4
4
4
4
5
4
5
4
8
3
8
3
6
6
9
1
3
N
N
N
0
0
M
N
0
Data
length
0
N
0
N
0
N
0
N
0
0
0
0
N
0
N
0
0
®
Quantum
Evaluating the bandwidth used by TCP/IP Modbus
messaging is particularly complex. This is because
many parameters change during each transaction
request from the application program:
b
Transaction periodicity is not simple to determine.
The request can be sent at a time when the task is already
under way, and the response also varies according to the
actual moment when the destination station performs the task.
If the network is particularly heavily loaded, the response may
take several periods.
To define the transaction period, these parameters must be
evaluated.
b
v
(in bytes) due to successive encapsulations: Ethernet (26),
IP (24), TCP (24) and Modbus-MBAP (7). This gives a total of
81 bytes. Another 12 bytes are added that correspond to the
inter packet gap.
v
the length of the Modbus protocol data unit (PDU) request/
response and its parameters. The different cases are listed in
the table opposite (value in bytes).
Note:
(1) N = Number of coils/8 or
(2) N = Number of inputs/8 or
(3) N = Number of registers x 2
(4) Ki = Length of object i, with i = 1 to n,
To evaluate the bandwidth used by Modbus TCP/IP
messaging, the following parameters must be defined
for each transaction:
1
2
3
The network load of the Modbus TCP messaging
service in bps can be evaluated using the following
formula:
(186 + size of the request Modbus PDU + size of the
response Modbus PDU)
x
8000/message send period
The calculation must be performed for peripheral
devices scanned at each transaction.
Evaluation of the TCP/IP Modbus
Transaction periodicity
Message length:
One part of the message always has the same length
The length of the second part of the message depends on
Message send period
Size of the request Modbus PDU
Size of the response Modbus PDU
N = Number of coils/8 + 1 (if remainder ≠ 0)
N = Number of inputs/8 + 1 (if remainder ≠ 0)
where n = number of objects
in ms
in words
in words
™
®
messaging
in ms
in bytes
in bytes
6/31
10
10
1
1
2
2
3
3
4
4
5
5
6
6
7
7
8
8
9
9