Conversion Tables: Weights & Measures, Metric

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Conversion tables - weights and measures

Some handy conversions for common measurements used by spa and hot tub owners are provided below, plus other helpful formulas and information. NOTE: Most figures are close rounded approximations.

See also: Figuring Spa's Water Volume

U.S. to Metric

Capacity

1/5 teaspoon = 1 milliliter

1 teaspoon = 5 ml

1 tablespoon = 15 ml

1/5 cup = 50 ml

1 cup = 240 ml

2 cups (1 pint) = 470 ml

4 cups (1 quart) = .95 liter

4 quarts (1 gal.) = 3.8 liters

Weight

1 fluid oz. = 30 milliliters

1 pound = 454 grams

Metric to U.S.

Capacity

1 milliliter = 1/5 teaspoon

5 ml = 1 teaspoon

15 ml = 1 tablespoon

30 ml = 1 fluid oz.

100 ml = 3.4 fluid oz.

240 ml = 1 cup

1 liter = 34 fluid oz.

1 liter = 4.2 cups

1 liter = 2.1 pints

1 liter = 1.06 quarts

1 liter = .26 gallon

Weight

1 gram = .035 ounce

100 grams = 3.5 ounces

500 grams = 1.10 pounds

1 kilogram = 2.205 pounds

1 kilogram = 35 oz.

Household Measurement Equivalents

16 tablespoons = 1 cup

12 tablespoons = 3/4 cup

10 tablespoons + 2 teaspoons = 2/3 cup

8 tablespoons = 1/2 cup

6 tablespoons = 3/8 cup

5 tablespoons + 1 teaspoon = 1/3 cup

4 tablespoons = 1/4 cup

2 tablespoons = 1/8 cup

2 tablespoons + 2 teaspoons = 1/6 cup

1 tablespoon = 1/16 cup

2 cups = 1 pint

2 pints = 1 quart

4 quarts = 1 gallon

1 gallon = 231 cubic inches

1 gallon water = 8.34 pounds

3 teaspoons = 1 tablespoon

48 teaspoons = 1 cup

1 teaspoon = 1/6 ounce

6 teaspoons = 1 ounce

1 tablespoon = 1/2 ounce

2 tablespoons = 1 ounce

Water Weight

	Pounds	Grams	Kilograms
Cubic centimeter	0.0022	1	0.001
Cubic inch	0.036	16.4	0.016
Liter	2.2	1000	1
Gallon	8.35	3785	3.8
Cubic foot	62.4	28317	28.3

See also: Figuring Spa's Water Volume

PPM (parts per million in water)

1 ppm + 1 mg/L

Electrical Formulas

amps x volts = watts
volts = amps x resistance (in ohms)
resistance = volts / amps
1000 watts = 1 kilowatt
1 kilowatt hour (kWh) = 1000 watts used for 1 hour

Estimating the Cost of Power Consumption

You can calculate the average operating cost of any electrical appliance by using the following formula, which multiplies kilowatt hours by the electrical rate:

Calculating electrical power consumption kWh x kWh rate = cost
(kilowatt hours used x power company rate = cost)

Example:
What is the monthly cost to operate a spa heater rated at 4,000 watts running for 3 hours per day in heating mode, with a local electrical rate of $0.08 per kilowatt hour?