Write protection
Sym‐
bol
ID
Read measured values on
the display
Read parameters on the
display
Change parameters
via the device with
display
Switch enabled
L
Yes
Yes
No
User PIN
1)
enabled
LP
Yes
Yes
Yes, after input of the
user PIN
Button lock enabled
LL
Yes
No
No
1)
The user PIN is factory set to 2457 in the device. When delivered, write protection is disabled
using the user PIN.
Devices with functional safety
To enable functional safety, first enable the User PIN.
7.3.2
Enable write protection with write protection switch
Introduction
The write protection switch is used for enabling write protection.
Procedure
1. Unscrew the cover.
2. Slide the write protection switch to the closed lock position.
Figure 7-8
Enable write protection using the write protection switch
Result
When the write protection switch is set to the closed lock position, measured values and
parameters can be read.
Operating (SITRANS TF)
7.3 Locking the device
SITRANS TH100/TH320/TH420/TR320/TR420/TF320/TF420 with 4 to 20 mA/HART
Operating Instructions, 05/2020, A5E41864807-AB
113