# POWER = MATH

*When it comes to power and how much is required to operate your van, it all comes down to simple mathematics. In this section, we tried to simplify how to grossly calculate how much power you need to operate your tools and equipment, either you use a generator, use your van's engine or plug in at your clients.*

## UNDERSTANDING ELECTRICITY

The following water analogy is pretty common, not perfect, but it will give you a good idea of how electricity works:

**AMPERES (current)**

*Shortened to Amps, or the letter A, or the letter I in an equation.*

Electricity consists of the flow of electrons through a conductor such as an electric wire - think of electricity as the flow/volume of water through a pipe. We measure the flow of electricity as an electric current, and electric current is measured in Amps. The bigger the current, the more electricity is flowing.

**VOLTAGE (pressure)**

*Shortened to Volts, or the letter V, and also the letter V in an equation.*

Electrical pressure is called Voltage. Volts are what makes the current flow in the first place, it's like a water pump that propels water through a pipe. It creates pressure in the pipe, causing the water to flow. Increasing the Voltage will make more current flow.

In North America, the domestic supply is typically 110V.

**WATTAGE (power)**

*Shortened to Watts, or the letter W, and also the letter W in an equation.*

Electrical power is measured in Watts, i.e. how much energy is released per second.

In some cases, you'll see that some equipments specify the "starting" Watts and the "running" Watts. This is easily explained by the fact that some equipments need a surge of power to start, then regularize to a lower Wattage.

**FORMULA**

When reading specifications for your tools and equipment, some manufacturers will only give one or some of the parameters. In any case, here is the formula to help you figure out the possible missing data:

**Volts (V) x Amps (I) = Watts (W)**

## HOW MUCH POWER DO YOU NEED?

Below is a list of the most common equipment aboard a grooming van. It might not be exactly what you have, but it will give you a good idea. It is impossible to list all brands, so many of these numbers are the industry average.

EQUIPMENT | DESCRIPTION | VOLTS | AMPS | WATTS |
---|---|---|---|---|

AIR CONDITIONING |
15,000 BTU | 120V | Average 16A | 3,500W for start up 1,500 to 1,950W running |

FANS |
Regular RV ceiling vent | 12V | Depends on speed 1.9 to 3A | 24 to 36W |

DRYER |
K-9 II Chris Christensen Kool Dry XPOWER B-8 Elite Pro |
120V 120V 120V |
18.5A 4 to 9.7A running - 11.7A start up 12A |
2,220W 1,350W start up - 1,025W running 1,440W |

CLIPPER |
Andis Wahl Oster |
120V 120V 120V |
0.2A 0.2A 0.4A |
25W 25W 45W |

CLIPPERVAC |
Mini ClipperVac | 120V | 7A | 840W |

VACUUM |
8 to 10 gallons ShopVac | 120V | 8.5 to 11.5A | 1,020 to 1,375W |

WATER PUMP |
Average RV water pump | 12V | 9A | 108W |

WATER HEATER |
If you use the electric back-up instead of propane |
120V | 12A | 1,440W |

REFRIGERATOR |
Average RV 3 cu. ft. mini-fridge | 120V | 5 to 8A | 350 to 600W |

MICRO-WAVE OVEN |
450 Watt 650 Watt |
120V 120V |
7.5A 10.5A |
900W 1,300W |

LIGHTING |
Fluorescent LED |
120V 12V |
About 0.3A per tube About 0.6A per meter |
About 32W per tube About 7.2W per meter |

RADIO |
Example for a satellite radio and 2 speakers |
12V | 5 to 10A | 50 to 200W |

BATTERIES/INVERTER |
Example for nightly top up of 2 x Outback 2000 batteries |
120V | 8A | 960W |

MISCELLANEOUS |
Phone charger DVD player |
120V 120V |
0.03A 1 to 1.5A |
4W 120 to 180W |

## IF YOU USE A GENERATOR (diesel or gas)

Most onboard generators in grooming vans are powerful enough to run several items concurrently - they usually allow 4,000 to 8,000W, so plenty of power to run many pieces of equipment concurrently.

You should still add the Wattage of all the equipment you might run a the same time to make sure your generator can take the load.

## IF YOU USE THE VAN'S ENGINE/ALTERNATOR

This set-up is hard for us to give you numbers, because many variables can affect them:

- Single or double alternator system?
- Fast idle switch?
- How many batteries?
- And many other elements which can change the power you have access to.

Although it might sound like using this set-up is very powerful, well, it's not. The most you can get is an average of 20 Amps/2,400W.

You are not getting the power from the engine with this set-up, but rather the engine is used to charge a battery bank, therefore, the amount of energy you have access to is very limited and rapidly depleted. You can always idle your van's engine, but even then, the batteries can't be recharged fast enough for you to have access to ample reliable power like with a generator.

## IF YOU PLUG IN AT YOUR CLIENTS

Most modern residential circuits in North America are 15 or 20 Amps (the breaker will be labeled either 15 or 20), so we're looking at a max load of either:

**20A Breaker = 2,400W**

**120V x 20A = 2,400 Watts**

**15A Breaker = 1,800W**

**120V x 15A = 1,800 Watts**

**IMPORTANT:** 1,800W or 2,400W before the breaker trips if the breaker is relatively new, older breakers will trip over a lower load.

Which means that whatever pieces of equipment that you want to run concurrently, cannot exceed a total of 1,800 or 2,400 Watts, depending on what is available at your client. A few more important notes to consider with this set-up:

- If you run the air conditioning, there are VERY few other equipments that you can use at the same time, if any (maybe the clipper, lights, radio). You might not be able to run the air conditioning at all if your client only has a 15A breaker.
- You can't run the air conditioning and a dryer at the same time (1,500W + 2,220W = 3,720W and the most you can have is 2,400W if your client has a 20A breaker).
- The plug your client will allow you to use on site doesn't mean it is a dedicated circuit for you and your equipment. The client may already have household items plugged on that circuit, therefore leaving you even less than 1,800 or 2,400W to use.