Specifications

PIP ELTFT01
March 2001 Field Inspection and Testing of
New Electrical Equipment
Process Industry Practices Page 7 of 23
5.3 The oil in all oil-filled equipment rated 69 kV and below shall be tested and shall
meet the values shown in the following table (based on NETA ATS-1999,
Table 10.4).
Test Value
Dielectric breakdown,
kV minimum
30
Dielectric breakdown,
kV minimum @ 0.04" gap
20
Dielectric breakdown,
kV minimum @ 0.08 gap
40
Interfacial tension
mM/m minimum
35
Neutralization number,
mg KOH/g maximum
0.03
Water content, ppm
maximum
25
Power factor at 25ºC, % 0.15
Power factor at 100ºC, % 1.50
Color 1.0
Visual condition Bright & clear
5.4 All ground resistance measurements shall be made by equipment utilizing the “fall of
potential” method per ANSI/IEEE Std. 81. Maximum ground resistance for all
electrical equipment is 5 ohms unless specified otherwise.
5.5 The test voltage for the DC step voltage test on medium-voltage switchgear and other
non-inductive equipment shall be as shown in the following table (based on NETA
ATS-1999, Table 10.11), unless specified otherwise by the Owner.
Insulation Class
Maximum
Field-Applied
DC Test (kV)
1.2 8.5
2.5 12.7
5.0 16.1
8.7 22.1
15.0 28.8
18.0 33.9
25.0 42.4
35.0 59.4
46.0 80.6
69.0 118.8
5.6 The maximum acceptable value of combustible gases for the transformer gas
chromatograph (GC) test is 500 ppm.