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Infrastructures (Air Conditioning)

Tringali, Soldani, Fiori, Paoletti, Passaquieti, Ruggi - 22:47 Saturday 21 November 2020 (49997)

WEB, NEB, MCB: HVAC switch-off test

This morning (windy day!), a selective switch-off test of heating ventilation air conditioning (HVAC) system has been performed at terminal buildings and Mode Cleaner building.
Below, time (LT) of each action and device are reported.

ID	Time (LT)	OFF	ON	Building	Device
1	8:58:00	X		WEB	AHU
2	9:08:00	X		WEB	Heater
3	9:18:00	X		WEB	Chillers
4	9:28:00	X		WEB	Hot water pump
5	9:38:00	X		WEB	Cold water pump
6	9:49:00	X		WEB	Air compressor 1
7	9:49:00	X		WEB	Air compressor 2
8	9:59:00		X	WEB	Air compressor 1
9	9:59:00		X	WEB	Air compressor 2
10	10:00:00		X	WEB	AHU
11	10:02:00		X	WEB	Heater
12	10:02:00		X	WEB	Chillers
13	10:03:00		X	WEB	Hot water pump
14	10:03:00		X	WEB	Cold water pump
15	10:15:00	X		NEB	AHU
16	10:25:00	X		NEB	Heater
17	10:37:00	X		NEB	Chillers
18	10:47:00	X		NEB	Hot water pump
19	10:57:00	X		NEB	Cold water pump
20	11:08:00	X		NEB	Air compressor 1
21	11:08:00	X		NEB	Air compressor 2
22	11:18:00		X	NEB	Air compressor 1
23	11:18:00		X	NEB	Air compressor 2
24	11:19:00		X	NEB	AHU
25	11:20:00		X	NEB	Heater
26	11:21:00		X	NEB	Chillers
27	11:22:00		X	NEB	Hot water pump
28	11:22:00		X	NEB	Cold water pump
29	11:32:00	X		Mode Cleaner	AHU 1 (sx)
30	11:42:00	X		Mode Cleaner	AHU 2 (dx)
31	11:52:00	X		Mode Cleaner	Chillers
32	12:02:00	X		Mode Cleaner	Cold water pump
33	12:12:00		X	Mode Cleaner	AHU 1 (sx)
34	12:22:00		X	Mode Cleaner	AHU 2 (dx)
35	12:32:00		X	Mode Cleaner	Chillers
36	12:42:00		X	Mode Cleaner	Cold water pump

Comments to this report:

Tringali, De Rosa, D'Andrea, Fiori, Paoletti, Passaquieti, Ruggi, Soldani - 18:19 Thursday 03 December 2020 (50091)

Magnetic glitch inspection @ WEB, NEB

From a preliminary investigation of HVAC switch-off test, we observe two families of magnetic glitchesin around 50 Hz covering the frequency bands ~(40-60) Hz and ~(20-80) Hz, respectively.
The glitches are visible in the magnetometers in the experimental hall. The current position of magnetometers are reported in the following entry #49422.

We identified the sources of the two glitch families:

switching-on of water chillers for glitches in ~(20-80) Hz--> there is a clear coincidence of single glitch with chiller current sensors (NEB and WEB);
switching-on of air compressors for glitches in ~(40-60) Hz --> these glitches diseappeared while the devices were turned off (NEB and WEB).

Moreover, we observe that other magnetic structers are always present in the WEB magnetometers and it seems they do not depend on the devices investigated so far. To be investigated.

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Tringali, De Rosa, D'Andrea, Fiori, Paoletti, Passaquieti, Ruggi, Soldani - 17:46 Wednesday 09 December 2020 (50169)

Inspection @ MCB

In the table, we summerize the lines associated to selective switch-off of HVAC devices at Mode Cleaner building and we highlight a couple of lines:

25 Hz associated to cold water pump and visible in the episensors on the floor (seismic) and hall microphone (acoustic)
48.8 Hz associated to chillers and visible in the episensors on the floor (seismic)

Several lines are associated to AHU 1 and AHU 2 as listed below:

Freq (Hz)	Devices	Seismic	Magnetic	Acoustic
2.0	AHU 1 (left)		x
19.2	AHU 1 (left)	x	x	x
18.4	AHU 2 (right)	x	x	x
19.0	AHU 2 (right)	x
19.4	AHU 2 (right)	x
24.0	AHU 1 (left)	x	x	x
24.3	AHU 2 (right)	x		x
25.0	Cold water pump	x		x
26.0	AHU 1 (left)		x
28.8	AHU 1 (left)	x		x
36.8	AHU 2 (right)	x		x
37.8	AHU 2 (right)	x
38.4	AHU 1 (left)	x	x	x
47.4	AHU 2 (right)	x
48.7	AHU 2 (right)	x		x
47.9	AHU 1 (left)	x
48.8	Chillers	x
56.3	AHU 2 (right)	x
56.8	AHU 2 (right)	x		x
57.5	AHU 1 (left)	x
65.8	AHU2 (right)	x
66.2	AHU 2 (right)	x		x
67.2	AHU 1 (left)	x		x
72.2	AHU 1 (left)	x		x
73.0	AHU 2 (right)	x		x
75.0	AHU 1 (right)	x		x
75.8	AHU 2 (right)	x
76.2	AHU 2 (right)	x
76.8	AHU 1 (left)	x		x
84.0	AHU 2 (right)	x		x
85.2	AHU 2 (right)	x		x
86.4	AHU 1 (left)	x		x
94.8	AHU 1 (left)	x

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Tringali, De Rosa, D'Andrea, Fiori, Paoletti, Passaquieti, Ruggi, Soldani - 19:03 Friday 18 December 2020 (50165)

Inspection @ NEB and WEB

At first glance, during the switch-off of all devices, it seems that the level of floor noise (seismic, magnetic and acoustic) at WEB is higher than that at NEB. It is worth reminding the wind conditions were bad during the switch-off actions.
Below, we recap the lines associated to HVAC devices at NEB and WEB, respectively. Most of them are generated by air handing unit (AHU) in both buildings.
We poin out the following lines:

@NEB

13.5 Hz associated to AHU fan and visible in the guralp on the floor (seismic)
24.9 Hz associated to AHU engine and visible in the guralp on the floor (seismic) and hall microphone (acoustic)
47.5 Hz associated to hot water pump and visible in the guralp on the floor (seismic)
48 Hz associated to cold water pump and visible in the guralp on the floor (seismic) and hall microphone (acoustic)
48.7 Hz associated to chillers and visible in the guralp on the floor (seismic)

Freq. (Hz)	NEB devices	Seismic	Magnetic	Acoustic
6.8	AHU	x	x	x
13.5	AHU - fan	x
24.9	AHU - engine	x		x
25.1	AHU		x
26.8	AHU	x		x
33.1	AHU	x
33.5	AHU			x
34.1	AHU			x
40.2	AHU	x	x	x
43.2	AHU		x
47.5	Hot Water Pump	x
48.0	Cold Water Pump	x		x
48.7	Chillers	x
53.8	AHU	x		x
56.8	AHU		x
61.4	AHU	x
67.0	AHU	x		x
73.8	AHU	x
76.8	AHU		x
83.6	AHU		x
87.2	AHU	x

=================================================================================================
@WEB

24.9 Hz associated to AHU engine and visible in the guralp on the floor (seismic) and hall microphone (acoustic)
47.3 Hz associated to hot water pump and visible in the guralp on the floor (seismic)
47.8 Hz associated to cold water pump and visible in the guralp on the floor (seismic) and hall microphone (acoustic)
48.6 Hz associated to chillers and visible in the guralp on the floor (seismic)

Freq (Hz)	WEB Devices	Seismic	Magnetic	Acoustic
5.4	AHU	x		x
24.9	AHU - engine	x		x
26.7	AHU	x		x
42.8	AHU	x		x
47.3	Hot water pump	x
47.8	Cold water pump	x		x
48.6	Chillers	x
53.2	AHU			x
58.9	AHU	x		x
74.5	AHU	x		x
93.2	AHU	x		x

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