Why am I getting an ERROR 18?

During the calibration process, ERROR 18 is displayed. The load cells are not the problem and all the configurations are OK. What else could be the problem?

On the HI 2151/20WC, HI 2151/30WC and the HI 2110WI, an "ERROR 18" is displayed because the difference between ZERO and SPAN is less than 100 counts in the positive direction.

There are two places during HARD CAL where "ERROR 18" can occur, at the ZERO entry and at the SPAN entry.

1. At the ZERO entry: The new Zero Reference (ZRCNT) is larger than the original Span (FSCNT) due to a large deadload. Skip ZERO and arrow to SPAN. After placing weight on the scale and running the span setting, "SPAN GOOD" is displayed. Arrow back to ZERO, remove weight and run Zero setting.  Once ZERO is done, reset the SPAN again.

2. At the SPAN entry: The millivolt signal reading did not show a positive increase. This may be due to:

a. Load cell may be installed upside-down.

b. Mechanical binding restricts the scales movement.

c. Load cell wires disconnected or improperly wired.

d. Improper load sharing or mechanical loading on the load cell.

e. Mechanical binding can mask weight readings.

f. Possible configuration error or memory corruption.

g. Verify the millivolt signal increases in the positive direction when weight is applied by using a DVM and measuring the MV signal across the + and - Signal connection.

See attachment for memory clear procedures. WARNING! This process returns the instrument to factory default parameters. Verify the SMM is in place when clearing process memory.

If unit still fails to calibrate properly, it would need to be returned to the factory for evaluation / repair.