Eagle Microsystems LCWA-HI - Manual (Page 6)

LC-WA HI IB.doc
9/16/04
f. If the output signal is greater than 15 millivolts, the load cell should be replaced with a
known good one.
LOAD CELL VOLTAGE CHECK (WITH 15V EXCITATION)
BLACK TO WHITE: +7.5V (EXCITATION / 2)
BLACK TO GREEN: +7.5V (EXCITATION / 2)
BLACK TO RED: +15V
LOAD CELL OUTPUT
GREEN TO WHITE: LESS THEN +/- 5 MILLIVOLTS (NO DEAD LOAD)
LESS THEN 25 MILLIVOLTS (EXACT OUTPUT
VOLTAGE DEPENDS ON DEAD LOAD WEIGHT)
BLK -EXT
GRN +SIG
RED +EXT
YEL SHLD
WHT -SIG
LOAD
CELL
LOAD CELL WIRING
FIGURE 4
N O T E : If the load cell's zero has shifted due to a mechanical overload, the reason for the
overload should be determined before a new load cell is installed.
4.3 REPLACING THE LOAD CELL
Call the factory to advise that the load cell is defective. Report model and serial numbers for load cell.
1. Disconnect the upper mounting plate from the vessel and remove all weight from assembly
2. Remove the screws from Summing Box lid. Disconnect the wires of defective load cell
being replaced. Gently pull cable out of the frame.
3. Use 3/4 wrench to remove 2 hext head cap screws which secure load cell to the base plate.
Remove the upper mounting plate and shock pad from the damaged cell and reinstall on the
replacement cell.
4. Install new load cell on the base plate using 35 ft. lbs. torque to screws and fish wires back to the
Summing Box.
5. Insert leads into terminal as before and tighten. Put lid on Summing Box and tighten.
6. Shim, if necessary to achieve even loading on the load cells.