Dry type transformers

Dry Type Transformers

Three-phase transformers auto refrigerated

KVA	Average noise level (dB)	Average noise level (dB)
KVA	Open	Encapsulated
0-9	40	45
10-50	45	50
51-150	50	55
151-300	55	57
301-500	60	59
501-700	62	61
701-1 000	64	63
1 001-1 500	65	64
1 501-2 000	66	65
2 001-3 000	68	66
3 001-4 000	70	68
4 001-5 000	71	69
5 001-6 000	72	70
6 001-7 500	75	71
7 501-10 000	79	72

Open three-phase transformers refrigerated forced air

KVA	Average noise level (dB)
0-1167	67
1 168-1 667	68
1 668-2 000	69
2 001-3 333	71
3 334-5 000	73
5 001-6 667	73
6 668- 8 333	75
8 334-10 000	78

Single-phase transformers self- refrigerated

KVA	Average noise level (dB)	Average noise level (dB)
KVA	Open	Encapsulated
0-50	50	50
51-167	55	55
168-333	60	60
500	64	63
833	65	64
1 256	68	66
1 667	70	68
2 500	71	70
3 333	72	71
5 000	73	72
10 000	79	72

Open single-phase transformers refrigerated forced air.

KVA	Average noise level (dB)
0-50	67
51-167	67
168-333	67
500	67
833	68
1 256	70
1 667	71
2 500	72
3 333	74
5 000	76
10 000	78

The data included in the tables are based on the Colombian technical standard NTC 5978.