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Getting Started

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As a facility manager, you know better than anyone that electrical power is the lifeblood of business. Without it, computers don't compute, pipes freeze, food spoils, machines don't run.

An electric utility power line has a profound effect on your bottom line. When you're without it, you need reliable temporary power.

This "Rental Power Planner" can help you plan effectively to secure rental generators and: can help you plan for power outage.You can use this booklet to develop a plan or refine the temporary power strategy you already have in place.

Getting Started: A Three-Step Approach

Although critical, planning for power need not be difficult. Here are three simple steps that will help you secure and maintain the rental power necessary to carry your facility successfully through a scheduled or emergency shutdown:

Step 1: Determine Your Facility Electrical Load. Before you rent temporary power, you have to know how much you need.

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If you have to keep your whole facility operating as it would with utility-supplied power, you need to determine your aggregate electrical load.

The quickest, easiest and most accurate way to do this is to take ammeter readings of your electrical distribution boxes. Take the reading when your company is normally operating at peak load. You can also obtain peak demand readings from your utility bills.

Aggregate loads are also listed on panels of electrical distribution boxes themselves. A statement of your total electrical capacity is also available at the local utility. However, these sources will not give you true readings of the temporary power you need since all buildings are wired for more electricity than they will use.



Priority Power

At times, you may want to power only those electrical loads that serve critical functions at your facility. If so, you need to prioritize individual loads.

If you're not sure what your critical loads are, start by determining the lost profit or other problems that result if your company is without the equipment. Other than life-safety electrical loads powered by your standby generator sets as required by law, examples of critical loads include: 

Lights- Heating, ventilating and air conditioning (HVAC)- Computers- Process equipment - Pumps

Prioritizing will help you decide which loads require power immediately during an emergency. This is important since it may take several hours or longer to secure all of the rental equipment you need on site during a large scale emergency, such as a natural disaster.

In most buildings, a separate distribution box will feed critical loads. In this case, you may only need enough temporary power for the loads served by that set of circuit breakers.

You can also decide to power specific critical loads served by separate circuit breakers within a distribution box. To do so, take an ammeter reading of the distribution box during the off-hours at your facility with the equipment you don't need shut off and the critical loads on. The ammeter will tell you how much power you need to serve the critical loads since that is all the distribution box is feeding. However, it's important that the non-critical loads are shut off and kept off when rental power is hooked up.

If you want to power individual pieces of equipment that use motors, amperage and voltage information is listed on nameplates. You can list this information and all your power needs on the work sheet in this booklet.

An additional note: Rental power is often used to back up standby generator sets during scheduled and emergency outages. To find out how much temporary power you need for standby service, contact the company that supplied the standby generator, or qualified rental generator set dealership.