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Energy saving operation and energy savi ng monitor
(6) Annual power saving amount, power charge (Pr. 899)
⋅By setting the operation time rate [%] (ratio of time when the motor is actually driven by the inverter during a year)
in Pr. 899, the annual energy saving effect can be predicted.
⋅When the operation pattern is predetermined to some degree, the estimated value of the annual power saving
amount can be found by measurement of the power saving amount during a given measurement period.
⋅Refer to the following and set the operation time rate.
1) Predict the average time [h/day] of operation in a day.
2) Find the annual operation days [days/year]. (Monthly average operation days × 12 months)
3) Calculate the annual operation time [h/year] from 1) and 2).
4) Calculate the operation time rate and set it to Pr. 899.
⋅Calculate the annual power saving amount from Pr. 899 Operation time rate (estimated value) and power saving
average value monitor
⋅The annual power saving amount charge can be monitored by setting the power charge per hour in Pr. 896 Power
unit cost.
Calculate the annual power saving amount charge in the following method.
Annual operation time (h/year) = Average time (h/day) × Operation days (days/year)
Operation time rate (%) = × 100(%)
REMARKS
⋅Operation time rate setting example: When operation is performe d for about 21 hours per day and the monthly average
operation days are 16 days
Annual operation time = 21 (h/day) × 16 (days/month) × 12 months = 4032 (h/year)
Operation time rate (%) = × 100(%) = 46.03%
Set 46.03% to Pr. 899.
Annual power saving amount (kWh/year) = × 24h × 365 days ×
Annual power saving amount charge = Annual power saving amount (kWh/year) × Pr. 896
REMARKS
In the regeneration mode, make calculation on the assumption that "power saving = power dur ing commercial power supply
operation (input power = 0)".
♦ Parameters referred to ♦
Pr. 3 Base frequency Refer to page 89
Pr. 52 DU/PU main display data selection Refer to page 141
Pr. 54 CA terminal function selection Refer to page 147
Pr. 158 AM terminal function selection Refer to page 147
Annual operation time (h/year)
24 (h/day) x 365 (days/year)
4032 (h/year)
24 (h/day)× 365 (days/year)
Power saving average value
(kW) during accumulation
when Pr. 898 = 10 or 9999
Pr. 899
100