Technical Data; Capacitance Values Of The Probe; Additional Capacitance; Input - Endress+Hauser Liquicap M FTI51 Operating Instructions Manual

Technical data

78
12 Technical data
12.1

Capacitance values of the probe

Basic capacitance: approximately 18 pF.
12.1.1

Additional capacitance

Mount the probe at a minimum distance of 50 mm (1.97 in) from a conductive container
wall.
Probe rod additional capacitance: approximately 1.3 pF / 100 mm (3.94 in) in the air.
Fully insulated probe rod in water:
• 10 mm (0.39 in) rod: approximately 45 pF / 100 mm (3.94 in)
• 14 mm (0.55 in) rod: approximately 74 pF / 100 mm (3.94 in)
• 16 mm (0.63 in) rod: approximately 38 pF / 100 mm (3.94 in)
• 22 mm (0.87 in) rod: approximately 50 pF / 100 mm (3.94 in)
Rod probe with ground tube:
• insulated probe rod: approximately 6.4 pF / 100 mm (3.94 in)
• insulated probe rod: approximately 38 pF / 100 mm (3.94 in)
• insulated probe rod: approximately 45 pF / 100 mm (3.94 in)
12.2

Input

12.2.1

Measuring range

Measuring frequency
500 Hz
Span
• ΔC = 5 to 1 600 pF
• FEI58: ΔC = 5 to 500 pF
Final capacitance
C = maximum 1 600 pF
E
Adjustable initial capacitance
• range 1 - factory setting
C = 5 to 500 pF
A
• range 2 - not available with FEI58
C = 5 to 1 600 pF
A
The minimum change in capacitance for point level detection
≥ 5 pF
12.2.2 Minimum probe length for nonconductive media < 1 µS/cm
The minimum probe length can be calculated using the formula:
Liquicap M FTI51
Endress+Hauser