CHOOSING THE BEST GENERATOR FOR THE JOB

Here are some things to consider when selecting a generator:

HOW DO YOU PLAN TO USE YOUR GENERATOR? - Generators are used to perform a wide variety of tasks, and Genpro offers a variety of models to suit almost all potential users. Genpro generators provide a high quality power source that is reliable and convenient.

  • Home Standby Power
  • Construction
  • Industrial
HOW QUIET DOES YOUR GENERATOR NEED TO BE?

Genpro generators are known for quiet operation. Genpro has sourced exceptionally low-noise models.
Home standby and construction applications would be satisfied with the models we offer.

IS ELECTRIC START REQUIRED?

Genpro generators are renowned for the ease of starting, and all our models have the convenience of electric start for applications that may require remote start or where the ease of electric start is preferred.

HOW MUCH POWER DO YOU NEED?

Generators produce AC voltage, very similar to the voltage available in your home, however while ESKOM produces sufficient power for all your electric powered devices, a portable generator is limited in power output directly relational to the engine horsepower. The amount of power that a generator can produce is rated in watts. Rated power is generally 90% of maximum power as certain components lose efficiency as they are heated from use.
To determine wattage requirements you should determine which devices need to be powered simultaneously and what the starting requirement of the device is. A Sizing Calculator is provided to assist you. Remember that with simple "Power Management" techniques, a small generator can provide adequate power for home or recreational applications.

“MAXIMUM” AND “RATED” POWER

A generator should never be operated at its MAXIMUM power output for more than 30 minutes.
RATED power, or the power that a generator can produce for long periods of time, is a more reliable measure of generator power. Typically the RATED power is 90% of the MAXIMUM power.
For Example, a 2500 watt generator produces a MAXIMUM 2500 watts of power. This means at maximum power this generator could light up 25 100-watt light bulbs at the same time. The rated wattage of this generator would be 2300 watts and should only be used to power 23 - 100 watt light bulbs.
When considering your power needs, first determine the highest power application such as a well pump for home power or air compressor for the job site. The power required to start the capacitor motor on these applications will determine the rated power of the generator you should choose for your application.

TYPES OF LOADS

In the previous example, the light bulbs are the LOAD of the generator. A 2500 watt generator can handle a LOAD of no more than 2500 watts maximum.

RESISTIVE LOADS: The light bulb example is called a RESISTIVE type load and the POWER it requires is pretty easy to understand. Other RESISTIVE types of LOAD are things like toasters, convection ovens, hot plates, curling irons, coffee makers, stereos and TV's. RESISTIVE LOADS are usually appliances that do not have electric motors.
RESISTIVE LOADS = 1 x Power
A REACTIVE load contains an electric motor. Some household appliances like a furnace or refrigerator have internal fans that come on intermittently, so extra wattage/power is needed to start the fan. Another example is power tools. An appliance or tool with a reactive load may require up to three times as much power (wattage) to START as it does to keep it running.
Examples of REACTIVE type loads:

    • Refrigerators / freezers • Furnace fans • Well pumps • Air conditioners • Bench grinders • Air compressors • Power tools
REACTIVE LOADS = 3 x Power
RESISTIVE LOADS:
The equation shows the relationship between watts, volts and amps in a PURELY RESISTIVE load. If you know any of the two variables, the third can be calculated.
Example: You want a generator to power a 1000 watt flood light. The light is 120V and requires 1000 watts of power. Using the equation, we can calculate that the floodlight will draw 8.3 amps of electrical current.
For REACTIVE loads, the equation shows only a general relationship between watts, volts and amps. That's because the power requirements for REACTIVE loads changes with operating conditions.
Resistive Loads – Volts x Amps = Watts

REACTIVE LOADS:
When determining the proper generator for REACTIVE type loads, you must consider three modes of operation:
STARTING - The electric motor requires more power to start. The starting power required can be up to THREE times the running amount.
RUNNING - The power required to run the electric motor once it has been started.
LOADED - When the electric motor begins to work (saw begins cutting wood, drill begins drilling thru a wall), its power requirement will increase. This is not applicable for most household appliances.
DATA TAG: Method 2 requires a visual inspection of the data tag supplied by the electric motor manufacturer. All electrical motors have a data tag attached to their bodies that give volts, amps, phase, cycles, hp, and sometimes a code.
Volts (V) - . Genpro generators are 240V. Amps (A) - Indicates the amps required to RUN the electric motor but doesn't consider STARTING or LOADED power requirements.
Phase (PH) - Genpro Generators can power only single phase motors only.
Horsepower (HP) - Rating of how much work an electric motor can perform.
Code - This isn't always provided on the data tag. It represents the maximum STARTING power required of the electric motor.

LOAD CODE: Is a letter which represents Amps per Hp to start the motor. Multiply CODE (amps) times Hp of motor to determine starting amps. For example: The data tag on our electric motor shows a code of L. Our motor is 1/3 Hp. An L code is 84 amps per Hp x 1/3 (motor Hp) = 28 amps to start the motor shown.