Calculated probe set up – SOR Multi Point RF Level Switch User Manual
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Form 677 (05.13) ©SOR Inc.
Calculated Probe Set up
Inject the picofarad equivalent
of maximum level from line 11 of the
worksheet. Watch the probe loading LED:
LED is on — close DIP switch
1 and go to step 2.
LED is off — go to step 3.
LED is on — close DIP switches
1 & 2 and go to step 3.
LED is off — go to step 3.
Turn the span pot CW until the probe
loading LED lights, and then CCW to
the point where the LED goes off.
Slowly cycle the LED on and off
as required to find the precise threshold
at which the LED goes off.
Turn all set point adjust pots
fully CCW (25 turns CCW).
Turn all on and off delay pots
fully CCW (one turn pots).
Set all fail safe switches to
LO
position.
Continue with Calculated set point set up
on the page which matches the first three
digits of the model number.
661.......p. 14
662.......p. 16
663.......p. 18
664.......p. 20
665.......p. 22
666.......p. 24
667.......p. 26
668.......p. 28
3000pf
2200pf
5200pf
4450pf
L
700pf
Solve for pf/ft.
Solve for pf/1 ft.
Level A 10’ 2200pf
-Level B -8’ -1900pf
pf /ft. 2’ = 300pf
pf 300 =150pf/ft.
ft. 2
30’
25’
20’
15’
10’
5’
0’
30’
25’
20’
15’
10’
5’
0’
30’
25’
20’
15’
10’
5’
0’
30’
25’
20’
15’
10’
5’
0’
30’
25’
20’
15’
10’
5’
0’
Solve for C in ft.
Convert C to pf
Max Level 30ft.
-Level A -10ft.
C 20ft.
C 20ft.
x pf/ft. x150pf
C in pf 3000pf
Solve for Max Level in pf
C 20’ = 3000pf
+Level A + 10’ = 2200pf
Max Level 30’= 5200pf
Solve for H in pf
Solve for pf @ Zero ft.
Max Level 30ft.
x pf/ft. x 150pf
H 4500pf
Max Level (pf) 5200pf
-H -4500pf
pf @ Zero ft. 700pf
Set point 25ft.
x pf/ft. x 150pf
L 3750pf
L 3750pf
+ Zero ft. + 700pf
Set point 4450pf
C=20’
Convert Set point to pf
Add zero value to L
5200pf
H
700pf
ft