The problem of OFL contains 4 situations:

Weight overflow,

weight underflow,

The signal of loadcell too low,

The signal of loadcell too high.

There are 4 reasons that can trigger OFL:

First: Indicator parameters setup error,

Second: external wiring error,

Third: loadcell damage,  

Fourth: Indicator hardware damage.

The equipment needed for OFL detecting:

A weighing platform with full scale of 20kg,

A GM9907-LD Weighing Indicator,

A weight of 2kg,

A straight screwdriver and a digital multimeter with millivolt voltage range.

Now please follow steps in the video to find out OFL reasons.