Siemens LC 500 사용자 설명서

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SITRANS LC 500 – INSTRUCTION MANUAL 

7ML19985GE01

If you are unable to change settings: 

• check that keylock level (menu 1F) is set to 0: the display should read PL = 0
• check that menu 01 is set appropriately: if Pv = 1, changes can only be made via 

HART

If you can change settings:

• reset menu 12 to factory settings: press both buttons, and the display should 

read FAC A

If the LCD displays a negative reading, typically around minus 300 pF, this often indicates 
a short circuit in the probe assembly:

• check the enclosure and make sure no water has got in
• check that all the connections in the probe assembly are solid