Earned Hours (E-Hrs) illustrates actual production quantity as a measure of time; specifically, the ‘expected’ hours required to produce the achieved quantity of product according to the product planned takt time. Earned Hours provides a measure of process efficiency when compared to the actual production hours consumed; if earned hours exceeds production hours, then the observed line’s performance exceeded the expectation per the standard.
Definitions and Calculations
Earned Hours = (Actual * Planned Takt Time) / 3600
- Actual is the amount of product actually produced during the Pitch, Shift, Day, or Week
- Planned Takt Time is the time planned to produce one unit of a product; this is the Line Cycle Time based on the Actual Product and the Operator Count for the Pitch, Shift, Day, or Week.
The Line Pitch Board (Production > Pitch Board) contains the information required to calculate E-Hrs values. On the Pitch Board, the line total E-Hrs values for the shift and week are represented as fractions of the total production hours during the specified shift for that day or week.
Changeover Earned Hours = per_pitch_EA_per_second * production_seconds
- per_pitch_EA_per_second = changeover_duration / total_production_seconds
Pitch Calculation
Example: Pitch actual production is 154 units and operator count is 1.71; the line cycle time for the product made is 24.15 seconds for 1 operator and 22.38 seconds for 2 operators.
E-Hrs = (154 * 24.15 ) / 3600 = 1.033
For fractional operator counts (ex. 1.71) during a pitch, the greatest specified operator count value (1 in the example above) that is less than the actual operator count is used for calculating E-Hrs.
Multiple-Pitch Calculation
Example Data: Each row is data for a pitch; data acquired from the Pitch Board is in white; calculated values are in yellow.
- E-Hrs per Pitch = (Actual per Pitch * Planned Takt Time) / 3600 = (184 * 9.76) / 3600 = 0.5
- E-Hrs all Pitches = SUM (E-Hrs per Pitch) = 0.5 + 1 + 1 = 2.5
Under Production > Settings, the label for both the E-Hr metric can be customized as well as the numerical precision (decimal places). The equation for the metric is also available.