LINK Systems 5100-8 Tonnage & Analog Signal Monitor - Manual (Page 66)

Doc #: L-802-1110 Page 64 Rev. 02
WARNING: Extreme care should be used in calibration procedures for tonnage
monitors. Severe damage to the machine being calibrated or the
calibration equipment can result from incorrect shut height adjustments.
Injury to personnel calibrating the machine or to others in the machine
area can result from poorly implemented load cell or hydraulic jack stacks
that fly out of the machine under load. NEVER place hands between
load cell or hydraulic jack stacks and the machine slide! Link Systems
provides calibration services at a reasonable charge. These services
should be used if there is doubt that customer employees can correctly
and safely calibrate a machine.
7.1 Dynamic Calibration with Load Cells
1) Check to see that the tonnage monitor is installed as per the installation instructions of this
manual.
2)
Turn on the power to the system. Observe that the tonnage monitor displays zero. If the
tonnage displays fail to zero within 40 seconds or an error occurs, check that the strain gages
are wired correctly into the channel connectors and refer to error conditions listed in this
manual.
3) Before calibration can proceed, verify that all configuration parameters are properly set.
NOTE: The machine rating must be set correctly before calibration and not
changed afterward. Changing the machine rating number after
calibration will result in incorrect tonnage readings.
4) If error conditions relating to setpoint limits occur, correct the invalid conditions and press the
RESET FAULT softkey.
5)
Set the high setpoint for each channel of the tonnage monitor to about 10% greater than the
tonnage expected on each channel when the machine is loaded at rated tonnage. The expected
tonnage for a two channel machine at full load is one-half (½) the rated tonnage of the
machine. For a four channel machine, the expected tonnage for each channel is one-fourth (¼)
the rated tonnage of the machine. For example, if a machine is rated at 200 tons the high
setpoint limits for each channel should be set to 110 tons (10% over ½ of 200 tons) if two
channels are used, or 55 tons (10% over ¼ of 200 tons) if four channels are used.
6) Set the low limits for each channel to zero (0).
7) Set the reverse limits for each channel to -10% of channel rating.
8) Bring the machine slide or ram to the bottom of the stroke and turn off power to the machine.
Place the load cell(s) to be used for calibration into position in the machine. Load cell(s) of
similar capacity and dimension are preferably centered under each drive connection to the slide
or ram of the machine. Also place any parallels or similar thickness plates on or under the load