14
Apply force slowly and symmetrically. A weight applied quickly can far exceed
the weigher limit. If using dead weight, align center line of weight to center
line of scale.
7. If the weigher indication falls outside the tolerances given in Section 1.3 at any points, recalibrate the
weigher following the calibration instructions given in Section 5.0 below.
5.0
Calibration Instructions
After performing the test outlined in Section 4.0, Calibration Verification, calibration of the PW 400/PW 500
is needed if the weigher indication exceeds the tolerances described in Section 1.3.
Factory calibration is performed using a calibrated hydraulic press to apply the required force loads. Dead
weights can be used to apply the required loads, however, it is recommended for safety reasons to use a
hydraulic press for calibration. Accuracy of the press must be .25 %or better (prefer .1% accuracy). If the
appropriate equipment is not available, return the unit to Rice Lake Weighing Systems for calibration.
1. Remove the Platform and Display cover as described in Sections 3.2 and 3.4.
2. Referring to Figure 3 on page 10, locate the switch SW1 on the PC Board. Set switch #4 to ON.
3. Reassemble the Platform to the base as instructed in Section 3.14.
4. Position the weigher on the press/surface to be used for calibration.
5. Connect the display cable to the J5 receptacle located on the PC Board. Position the display cover
assembly so that the display will not short circuit to the base and will not interfere with the platform.
6. Place the RST-OFF/ON to the ON position. The display will read “BUS ADDRESS=XX”, “CAL
ROUTINE”, and “ZERO FOR CAL PTS”. Now quickly press the ZERO push button. The “ZERO
FOR CAL PTS” is a timed function, and if the ZERO button is not pressed in time the display will
show “SET SW 4 TO OFF”. If this happens, turn the weigher OFF then back ON and try again.
7. Place the 10 inch by 10 inch steel plate used for calibration verification on the weigher platform.
8. The display will show “EXERCISE TO 20K” and “THEN PRESS ZERO”. Apply a force to the
weigher platform equivalent to 20,000 lbs. Remove the force, then press the “ZERO” button. Repeat
this operation three times.
9. After exercising the weigher three times and pressing the“ZERO” button, the display will read “PT 1
READY” momentarily, then show “XXXX CNTS”. Apply a force of 1,000 lbs. to the weigher.
Allow the force indicator to stabilize and press the ZERO push button.
10. The display will show “PT 2 READY” momentarily, then show “XXXX CNTS”. Increase the force
to 5,000 lbs. Allow the force indicator to stabilize and press the ZERO push button.
11. The display will show “PT 3 READY” momentarily, then show “XXXX CNTS”. Increase the force
to 10,000 lbs. Allow the force indicator to stabilize and press the ZERO push button.
12. The display will show “PT 4 READY” momentarily, then show “XXXX CNTS”. Increase the force
to 15,000 lbs. Allow the force indicator to stabilize and press the ZERO push button.
13. The display will show “PT 5 READY”. Increase the force to 20,000 lbs. Allow the force indicator to
stabilize and press the ZERO push button.
14. After the #5 calibration point is entered, the display will show “SET SW 4 OFF”. Remove the force
on the weigher platform. Place the #4 switch on SW1 of the electronics PC Board to OFF position.
!
Caution
