What does the blinking LED's signify on my HI 2151/30WC?

The weight deviation in the upper range on our HI 2151/30WC has been growing slowly over the last couple of months. I noticed that the status LED's for Alarm 1 + 2 were blinking alternatively with the LED's for 'Zero Track' + 'Motion' + 'CTR Zero'. The weight reading on the display was normal. After switching the module off and on the LED's were still blinking. Measurement of Excitation, Sense and Signal wires gave normal results. The unit was switched off and on once again, after which the LED's were not blinking anymore. Could you give me an explanation for the blinking LED's? Could this also cause a weight deviation?

The blinking Alarm 1 & 2 LED's on your HI 2151/30WC indicate that the current weight reading meets the setpoint requirements for the relay setpoints. This would turn the relay on and cause the Alarm led to blink. This would not have any effect on the weight indications or response.

The blinking Zero Track, Motion, & CTR Zero LED's indicate that the unit will allow the operator into the calibration menu. This may have happened because someone changed the position of the #2 dip switch on the back of the unit, or they did not exit the calibration menu properly by hitting "ENTER" at "ENDCAL". Normally if you press the "CAL" button, it will ask for a security code to get into the CAL menu. If these LED's are flashing it will not ask for the security code.

NOTE: Once you enter the security code, these LED's will start flashing. They will normally continue flashing until you press "ENTER" at "ENDCAL" to exit the calibration menu. This will not have any effect on the weight indications or response. If you just press "EXIT" to get out the calibration menu these LED's will continue to blink until you exit properly as mentioned above.

If you are having problems with the weights at the higher end of the scale range, this would normally be caused by a binding issue or a bad load cell. If you add weight to the scale at the lower end and it responds correctly, but then after a certain weight it starts responding badly check the following:

1. Verify the LINCOR setting in the units' calibration was done correctly or is set to zero. If it was done incorrectly this could cause incorrect weight response at weights above the span value.

2. Check the inputs on individual load cells to see if the mV reading on one or more of them is out of range. (Disconnect the Sig leads of all load cells and measure the mV reading from each load cell and compare with others. They should all be about the same.)

3. Look for binding or flexure problems to the scale. You may need to disconnect all piping, hoses, etc. from scale/vessel and check linear reaction to see if load cell problem or piping problem.