Endress+Hauser Prothermo NMT81 - Hardware Locking or Unlocking

Prothermo NMT81 Operability
Endress+Hauser 49
Connector or switch Description
DIP switches (right): Compatibility mode of
NMT53x
ON: NMT53x compatibility mode
OFF: NMT81 mode
Default setting: OFF

For more details, →  71
Operating keys • For factory reset
• For unit (mm, inches, Celsius, Fahrenheit) setting
• For increment/decrement of level value
7.5.1 Hardware locking or unlocking
The parameter write access can be locked by the DIP switch (left) on the electronic insert.
In this locking state, all parameters are read only and the key symbol  appears on the
local display.
If operation is locked by means of the DIP switch, the operation is only unlocked again
by means of DIP switch.
1. Unscrew the housing cover.
2. Set the write protection switch (left) into the desired position.
 ON: operating menu is locked; OFF: operating menu is unlocked.
3. Put the display module onto the connection compartment, screw the cover closed.
This completes the write protection on/off procedure.
Indication of the locking state
000.00
K
0 10 20 30 40 50 60 70 80 90 100
A0044295
 45 Write protection symbol in the header of the display
Write protection via locking switch is indicated as follows:
• Locking status = Hardware locked
•  appears in the header of the display.