Air outlet temperature standard for air-cooled generators

Ambient temperature can be defined as the temperature of the surrounding air at a particular location. The internationally accepted standard value for industrial use alternators is 40°C. Ambient Temperature (40oC) Air inlet Air outlet `.

Cooling air supplied by shaft-mounted fan or separate blowers. 50 to 100 CFM per kW of losses. Oversized for a typical 20o C rise over ambient for the internal cooling circuit. Example: 40o ambient + 30o C = 70o C internal air. Ambient air temp remains constant.

3.1 DERATING DUE TO TEMPERATURE – The rating for NTP temperature is assumed as 70°F. Depending whether the engine prime mover is naturally aspirated, turbocharged and/or charge-air cooled, will determine the level of power available above 70°F.

• Generators may be rated on a stand-by basis (see 32.35). Temperature rise not to exceed Table 32-3 by more than 25º C. • For ambient temperature higher than 40º C, the temperature rise shall be reduced by the degrees that the ambient exceeds 40º C. • For totally enclosed water-air cooled machines, the cooling air.

For cooling air temperatures below 40ºC, International Standards allow the alternator’s rating to be increased by an appropriate multiplying factor from the following simple tables, but no further increase is allowed for temperatures below +10ºC.

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6 FAQs about [Air outlet temperature standard for air-cooled generators]

What is a good air temp for a generator?

For a generator, the internal inlet air temperature is typically 35-40 degrees Celsius higher than the ambient temperature. This is known as the Overdesign Temperature Rise (ODP). The generator does not require any de-rating for single-wall applications with typical cooling water temperatures of 32 degrees Celsius.

Can a generator air outlet be ducted?

If the engine room ventilation system cannot compensate for the temperature gradient caused by the hot air, the generator air outlet can also be ducted to allow the air to be exhausted outdoors. Open air cooling is the most typical solution for stationary indoor power plants. An open air cooled generator (IC0A1) with drip proof protection (IP23).

How much incoming air does a generator need?

A generator typically needs 35-40% over-sizing of the incoming air based on the internal generator inlet air temperature being ambient + 20 degrees Celsius. For typical 32 degrees Celsius water, there is no de-rate for single-wall application. The generator requires this amount of air for cooling purposes. For example, for every kilowatt of loss, the required flow is 1 gallon per minute.

How does a generator air outlet work?

The cooling air is typically drawn in through air filters, passed through the active parts of the generator, and then exhausted back to the environment. If the engine room ventilation system cannot compensate for the temperature gradient caused by the hot air, the generator air outlet can also be ducted to allow the air to be exhausted outdoors.

Can a generator run cooler at high altitude?

Generators specifically designed for high altitude may have a larger fan to partially compensate for reduced heat capacity of air, or could be oversized to run cooler under these conditions. Reduced ambient temperature at high altitude may partially compensate. Depends on allowable temperature rise and other factors; actual value may vary.

How many air cooled generators are there?

More than 130 generators of these new designs have been shipped through the end of 1992, with approximately on -half in service. Theair-cooled generator product line iscontin-uing to evolve. The generator that is being applied with the LM6000 aeroderivative gas tur-bine (Figure 13) was tested and shipped in 1992.

Air outlet temperature standard for air-cooled generators