LINK Systems 5100-8 Tonnage & Analog Signal Monitor - Manual (Page 68)

Doc #: L-802-1110 Page 66 Rev. 02
When load cell tonnages are equalized, again repeat the cycle of single stroking the machine
with shut height or other bottom of stroke adjustment between strokes and continue to observe
the tonnage on each load cell. It may be necessary to re-shim certain load cell stacks to
equalize tonnage on all load cells as rated tonnage capacity of the machine is neared. Rated
machine capacity of the machine is reached when individual tonnage on load cells equals the
rated machine tonnage divided by the number of load cells used to calibrate the machine. For
example, if four load cells are used to calibrate a 200 ton mechanical power press, the press is
loaded to capacity when each of the four load cells is loaded to 50 tons. When rated machine
tonnage, or a lesser tonnage at which the machine is to be calibrated is reached, lock shut
height adjustments and proceed to the next step.
Do not exceed rated tonnage capacity of the machine or load cells during the calibration
process by more than five or ten percent.
Vibratory motion in the machine often introduces stroke to stroke variations of one or two
percent in the load cell tonnage readings. When this happens it is impractical to try to refine
the load on the machine any closer than within one or two percent of rated tonnage.
13) After loading the machine to the tonnage at which it is to be calibrated as per the previous step
of this calibration procedure, go to the Tonnage Monitor Calibration screen (see section 4.5 on
page 47).
For a two channel OmniLink II tonnage monitor module:
Turn the RUN/PROG keyed selector switch to the RUN position and make single strokes
of the machine. The display will update the channel and total tonnage display each stroke
on the calibration screen. Between strokes, switch the RUN/PROG keyed selector switch
to the PROG position and enter cal. #s for both channels until channel 1 and channel 2
tonnages of the OmniLink II tonnage monitor module are within one or two percent of one-
half (½) the sum of the load cell readings.
For a four channel OmniLink II tonnage monitor module:
Turn the RUN/PROG keyed selector switch to the RUN position and make single strokes
of the machine. The display will update the channel and total tonnage display each stroke
on the calibration screen. Between strokes, switch the RUN/PROG keyed selector switch
to the PROG position and enter cal. #s for all channels until all four channel tonnages of
the OmniLink II tonnage monitor module are within one or two percent of one-fourth (¼)
the sum of the load cell readings
14) On machines with tie rod construction, go to the graph screen and verify that the tie rods are
properly tensioned. See section 7.4 on page 67 for details on how to do this.
15) Copy down the calibration numbers so that periodic checks for calibration can be made. It is
suggested that a copy of these numbers be retained inside the control enclosure and that a
second copy be kept in files.