﻿GET_GEVOMechL2_05_01_01_39 - ANIMATION Screen
1
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The sequence of shutter positions and fan speeds is based on the resulting air flow through the air-to-air intercooler and the subsequent manifold air temperature.

2
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With the shutters both open and the fans both off, some energy transfer occurs due to natural convection.

3
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Significantly more air flow and thus energy transfer occurs when one of the fans is on and both shutters are open.

4
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To limit the magnitude of the air flow change, the shutters are both closed when the first fan is turned on.

5
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The sequence explained above works in reverse for decreasing manifold air temperature.

6
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With both fans in service and both shutters initially open, as the temperature decreases, the first shutter is commanded closed.

7
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If the temperature is less than the lower set-point with the shutters at a minimum position (one shutter open, one shutter closed), the first fan to start is turned OFF, and both shutters are opened.

8
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If less cooling air flow is required, both shutters are then closed.

9
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When the temperature again drops below the lower set-point, the second fan is turned OFF and both shutters are commanded to the fully open position.

10
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The shutter position is then reduced from both open to one open, or to both closed or until manifold air temperature is no longer below the lower set point.

11
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To minimize the probability of fan motor bearing deformation and pitting on either fan due to inactivity, a condition referred to as brinelling, a fan is commanded to run for 10 seconds if the fan has been off for 30 minutes and the locomotive is not in the self-test mode.

12
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The table displays the air-based intercooler shutter and fan configuration.
