There are a number of items to check, in this order, before we conclude the balance needs to be returned for repair/replacement. After completing each item, measure a solid object with a known mass.
1. Make sure the balance pan is not locked. OHAUS locks the balance pan for shipping. You will find the locking knob on the underside of the balance pan. Turn the knob to unlock the balance.
2. Confirm that the proper pan (the pan that was shipped with the balance) is being used with the balance. You should not consider the OHAUS balance pans to be interchangeable.
3. Confirm that the pan is properly seated and there are no particles under the pan.
4. Make sure the Security Switch on the bottom of the balance is unlocked. This switch controls access to calibration functions and the ability to change units.
5. Make sure there is no significant air flow across the top of the balance. Air currents can affect a measurement, so do not place the balance near a fume hood, an open window, or a heating/cooling unit that operates intermittently.
6. Make sure the balance is level. Test this with a small bubble level, which OHAUS does not provide and Vernier does not sell. Most hardware stores carry these levels.
7. Calibrate the balance. Each OHAUS balance is shipped with a standard solid mass (the mass size varies depending on the model of balance purchased) which can be used to calibrate the balance. Please refer to the OHAUS Balance Owner's Guide for the calibration instructions.
If the balance still measures inaccurately after completing these checks, then contact Technical Support at firstname.lastname@example.org.