Siemens SIMATIC ET 200SP Function Manual

OPC UA communication
9.3 Using the S7-1500 as an OPC UA server
Communication
170 Function Manual, 11/2019, A5E03735815-AH
Rules
If write rights are required:
● AccessLevel = 2 oder 3
● "Writable from HMI/OPC UA" enabled
If read rights are required:
● AccessLevel = 1 (AccessLevel 3 is also possible, but misleading. The settings suggests
that an OPC UA client has write and read rights)
● "Accessible from HMI/OPC UA" enabled, "Writable from HMI/OPC UA" disabled
If neither read nor write rights are to be granted (no access):
● AccessLevel = 0
● "Accessible from HMI/OPC UA" disabled
Only one of the two conditions needs to be met to block all access. In this case, review
whether the tag in the OPC UA server interface is actually necessary at all.
Access table
"Accessible from HMI/OPC UA" must be set if access over OPC UA is to be possible at all.
"Writable from HMI/OPC UA" must be set to allow an OPC UA client to write a tag / DB
element.
Please see the table for the resulting access right.
Table 9- 2 Access table
OPC UA XML
STEP 7 (TIA Portal), for example tag table
AccessLevel
Accessible from
HMI/OPC UA
Writable from HMI/OPC
UA
Resulting access right
0
x
x
No access
x
0
x
No access
1
Enabled
x
Read only
2
Enabled
Disabled
No access
3 Enabled Disabled Read only
2
Enabled
Enabled
Write only
3
Enabled
Enabled
Read+write
(x = don't care)
See also
Consistency of CPU tags (Page 171)
Managing write and read rights (Page 165)

Siemens SIMATIC ET 200SP Specifications

General

System Type	Distributed I/O System
Mounting	DIN Rail
Communication Protocol	PROFINET, PROFIBUS
IP Rating	IP20
Category	I/O Systems
Supply Voltage	24 V DC
Modularity	Yes
Hot Swapping	Yes
Storage Temperature	-40°C to +70°C
Digital Inputs	Yes
Digital Outputs	Yes
Analog Inputs	Yes
Analog Outputs	Yes
Communication Interface	PROFINET, PROFIBUS
Number of Modules	Up to 64
Relative Humidity	5 to 95% (non-condensing)
Operating Temperature	-25°C to +60°C