B777 Hot Battery.
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B744 MEL
Message - BATT CHARGER MAIN Level - Status Condition - Main Battery charger failed or input power to charger failed, or interlock open or main battery overheat
No you can't monitor it as such but you will get a Status MSG.
B777 MEL Message MAIN BATTERY OVHT Level Status Basic Main battery over temperature.
Message - BATT CHARGER MAIN Level - Status Condition - Main Battery charger failed or input power to charger failed, or interlock open or main battery overheat
No you can't monitor it as such but you will get a Status MSG.
B777 MEL Message MAIN BATTERY OVHT Level Status Basic Main battery over temperature.
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What I am getting at, is that there is no checklist or procedure to reduce the overtemperature, a thermal runaway could become a serious problem.
There is obviously some built in safe guard, so I would like to know what it is.
There is obviously some built in safe guard, so I would like to know what it is.
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In the B777, the main battery is monitored and controlled by the Electrical Load Management System (ELMS). If an over-temp is detected ELMS automatiacally disconnects the battery.
From looking at the overhead panel, you can see that there are no controls (apart from turning the battery on/off) for the DC system. Control of the DC system on the B777 is fully automatic.
From looking at the overhead panel, you can see that there are no controls (apart from turning the battery on/off) for the DC system. Control of the DC system on the B777 is fully automatic.
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Thermal runaway occurs when there is a high charge rate, heat rises internal resistance goes down, which causes the charge current to go up which causes heat to rise which causes the IR to go down etc etc. The protection from this would be sensed by the battery charger, hence the message BATT Charger on the 744. So the charger will sense the increase charge rate and should cut it off, on the 777 (not sure about the 744) the battery temp is also monitored and should cut out on it's own.
I stand to be corrected but that's how I understand it, sort of!
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