Festo SOEL-RTD-Q50-PP-S-7L, Mounting And Operating Instructions, Page: 33 / 54

Festo SOEL-...1606d English 33
SOEL-
Difference hold mode
When the difference hold function is activated and Q
1
= +U
B
, this function detects the difference between the minimum and
maximum value of the measuring signal and stores it.
If Q
1
= -U
B
, the last differential value is transmitted at the analogue output.
Example of use: Checking the contents of open containers or packages.
Measured value hold mode
When this function is activated, the last valid measured value is saved.
When no object is in the measuring range, the last valid measured value is transmitted at the analogue output. The current
value is only displayed again when an object is within the measuring range (OK LED = on).
Example of use: Maintain position of tool during change-over of work piece when machining.
Behaviour of analogue output with and without measured value hold.
Start of measuring range
End of measuring range
With measured value hold
Without measured value hold
Analogue v
alue
Analogue output
Q
1
= +U
B
= Sample. Collect measured values
Q
1
= -U
B
= Display. Last maximum of analogue signal at
analogue output
A B B B
B
A
A
100% (20 mA)
0% (4 mA)
0% (4 mA)
12 mA
2 mA
1
1
2
2
1
2
100% (20 mA)
+U
B
-U
B
Q
1
100% (20 mA)
0% (4 mA)
0% (4 mA)
100% (20 mA)
Good Target Q
2
Illustr. 16
15500149
Illustr. 17
15500275
ON
OFF