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iPhone / iPad
  • Utilities
  • Productivity
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Have a look at my plus version, Watts Plus, for more features.

- Set the cost per Kilowatt-Hour (KWH)
- Select Amps, Watts, or Kilowatts
- Set the desired AC voltage (100 - 240 volts)
- Set the Power Factor, (use 100% if unknown)
- Set the amps, watts, or kilowatts slider
- Set the number of hours per day the appliance runs

- Touch the lock on either amps or watts to toggle the lock setting. The unlocked parameter varies when volts or power factor is changed.

- The cost per hour, day, month, and year is computed and displayed, based on hours per day usage entered.

- Previously entered values are remembered next time Wattulator is run.

The cost is only approximate, due to several factors:

- Cost per KWH is tiered by most power suppliers. Enter cost for the desired tier, but recognize that actual costs may be different depending on your power company's billing policies and total energy consumed.

- Power Factor is an estimate because appliance manufacturers don't typically specify a value. An incandescent light has about 100% power factor. An electric motor is in the range of 60% - 80%.