Flintec KPF-10 - Manual (Page 6)

C ORNER C ORRECTION AT S CALES WITH F LINTEC L OAD C ELLS
Flintec load cells are manufactured with rather tight tolerances, so in most cases an additional corner
correction is not required. The best conditions are achieved if you use load cells of the same class
(Designation is done with capital letters A to I on the load cell package besides the type label).
Hint: Corner errors can have a mechanical background, e.g. sloped mounting surface of the load cell.
Procedure:
1. Get the display value for each corner. Use the highest possible display resolution (e.g. factor 10 or
higher) or, if this is not possible, measure the the digital weight increment using corresponding weights.
2. The corner with the lowest display value is the starting point for the corner correction. The differences of
the other corners are calculated with reference to this “basic corner”.
3. Calculate the correction resistance as follows:
Deviation in [kg]
Correction resistance [
Ω] =
Test weight in [kg]
x Input resistance of the load cell [
Ω] *
* 1100
Ω input resistance for: BK2, SB4, SB5, SB6, SB14, SLB, ZLB, UB1, UB5, UB6, PB, RC3
400
Ω input resistance for: RC1, SB2
Example 1: 1100
Ω load cell
0.1 kg corner error with 500 kg test load
0.1 kg
500 kg
x 1100
Ω =
0.22
Ω
Example 2: 400
Ω load cell
10 kg corner error with 5000 kg test load
10 kg
5000 kg
x 400
Ω =
0.8
Ω
4. Install the correction resistor into the junction box for the corresponding load cell excitation.
New resistor = Correction resistance + 2.1
Ω (pre-installed resistor)
5. Check the corners again. If required repeat the procedure.
Hint:
50 ppm resistors for corner correction are available as a set of 14 values from 0.22
Ω to 4.7 Ω (10 pcs. for
each value; article no. 5200-030).
C LOSING THE J UNCTION B OX
In the junction box there are two dry tablets in a plastic bag. Unbag these pills and leave them within the
junction box .They will absorb moisture up to a certain degree.
Before you will close the junction box you must check the cover and the cover sealing for any dirt or damage.
Replace the cover sealing if required, otherwise a proper sealing is not assured.
Generally you have to use the red sealing made of silicone. You can improve the quality of this silicone
sealing (it must be the red one!) by using a suitable grease (e.g. sanitary grease for fittings).
The cover screws always have to be tightened crosswise and equally unless the cover is attached to the
junction box.
Generally the inside of the junction box must be totally dry before you can close the cover.
Junction Box Type KPF – Technical Manual, Rev. 1.11 July 2008
Page 6 of 8