Strange behavior of the extractor blower at the stock ramp of Carmel hospital « on: May 11, 2025, 04:39:31 AM » Author: dor123
When the extractor blower at the stock ramp of Carmel hospital being turned off and back on by the emergency generator of Carmel hospital, behaves like this: https://www.youtube.com/watch?v=7lTKYye_pis What is the reasons?
« Last Edit: May 11, 2025, 09:06:50 AM by dor123 »		Logged

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	Re: Strange noise of the extractor blower at the stock ramp of Carmel hospital « Reply #1 on: May 11, 2025, 05:18:06 AM » Author: AngryHorse
That sounded to me like they threw it in reverse?, either that or it’s got some form of DC break on it?, before the emergency kicks in?
« Last Edit: May 11, 2025, 05:27:41 AM by AngryHorse »		Logged

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	Re: Strange noise of the extractor blower at the stock ramp of Carmel hospital « Reply #2 on: May 11, 2025, 05:27:03 AM » Author: dor123
What is happening is that the motor slows down, than suddenly breaks and than speed up. There is a delay for several seconds before the breaking and speeding up. It don't spinning backwards. Why this is happening.
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I"m don't speak English well, and rely on online translating to write in this site.
Please forgive me if my choice of my words looks like offensive, while that isn't my intention.

I only working with the international date format (dd.mm.yyyy).

I lives in Israel, which is a 220-240V, 50hz country.

	Re: Strange noise of the extractor blower at the stock ramp of Carmel hospital « Reply #3 on: May 11, 2025, 05:31:04 AM » Author: AngryHorse
They must have to almost stop it before the emergency kicks in? Wonder if it’s something to do with disturbing the sine wave from changing to another supply? 🤔
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Current: UK 230V, 50Hz
Power provider: e.on energy
Street lighting in our town: Philips UniStreet LED (gen 1)
Longest serving LED in service at home, (hour count): Energetic mini clear globe: 59,462 hrs @ 7/4/25

Welcome to OBLIVION

	Re: Strange noise of the extractor blower at the stock ramp of Carmel hospital « Reply #4 on: May 11, 2025, 08:35:34 AM » Author: dor123
@Ash, @RRK, @Medved?
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I"m don't speak English well, and rely on online translating to write in this site.
Please forgive me if my choice of my words looks like offensive, while that isn't my intention.

I only working with the international date format (dd.mm.yyyy).

I lives in Israel, which is a 220-240V, 50hz country.