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5. TROUBLE SHOOTING
ZERO CALIBRATION
When the error messages appear on the display, the calibration is invalid. Follow theses
guide step by step to solve the problems.
1. A A A A A A A a. Poor connection
—To check the connector wirings
b. Wrong connection
—To check the Load Cell Connector to see if the polarity of
signal is reversed.
c. The input offset voltage signal is too low (over –1.5mV)
—To disconnect the power and insert a resistor (100–500K ohm)
* Between EXC + and SIG +, a 200K ohm resistor is normally
used
d. Load Cells is damaged.
—To replace with new Load Cells
2. U U U U U U U a. Poor or wrong connection
—To check the connector wirings
b. The input offset voltage signal is too high. (+2mV)
—The Load Cell capacity is too small or it is malfunction
Change new Load Cells with bigger capacities
c. Load Cells is damaged
-To replace with new Load Cells
d. Thunderstorm damage
—To replace a new A/D converter
* If there had been inserted a resistor already, use another resistor with greater
resistance.
SPAN CALIBRATION
1. L L L L L L L a. Wire connection is reversed at SIG+ & SIG-
—Check the Load Cell connector to see if the polarity of signal
is reversed
b. The load cell receipting direction is wrong
—Check all load cells for correction installation
2. C C C C C C C The calibrate weight is too light
–The calibrate weight should be at least 100 times of the
minimum division