IFM LK 022 Series, Operating Instructions Manual

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The indicated values for [OP] refer to the distance between OP and the
lower edge of the probe. The values apply if [OFS] = [0].
If [OFS] > [0], they increase by the set offset value.
Example LK1022: According to Table 12-2, OP has to be set to segment
20.4 cm.
[OFS] = 7.0 cm
[OP] is to be set to 20.4 cm + 7.0 cm = 27.4 cm.
13.3 Calculation aids [OP]
For proper functioning of the overflow prevention OP, a minimum distance
(y) (Fig. 12-1) must be observed (→ 6.1) .
The following applies (Fig. 12-1):
B + c = L + u
and
B = z + y
B: tank height
c: outside length (maximum
(→ 6) )
y: required response level OP
from the cover (minimum
(→ 6.1) , maximum (→ 13.2) )
L: probe length
u: distance between probe and tank
bottom
z: required response level OP from
the bottom (maximum: z < L - c - y
or z < B - y)
13.3.1 Definition "from the cover“
Required distance (y) of the overflow prevention OP
"from the cover" is defined.
• Without offset ([OFS] = [0]): [OP] = L - c - y
• With offset ([OFS] = u): [OP] = L - c - y + u
or
[OP] = B - y
Example:
c = 3.0 cm, y = 5.0 cm, u = 1.0 cm
Without offset: [OP] = 26.4 cm - 3.0 cm - 5.0 cm
= 18.4 cm
With offset: [OP] = 26.4 cm - 3.0 cm - 5.0 cm + 1.0 cm
= 19.4 cm
Fig. 12-1
OP
c
z
B
L