CA01082E_Catalog 30

Arrester Selection Guidelines Selecting the appropriate MCOV of a surge arrester is a critical step in the protection of vital utility equipment. The MCOV of an arrester should be selected to ensure it can withstand the maximum continuous line to ground voltage. The table below provides general guidelines for solidly grounded applications, as well as impedance or undergrounded circuits. A higher rated arrester may be required depending on the exact application. Please consult with Hubbell for additional support to select the appropriate MCOV for your specific application.

Normally Recommended Arrester MCOV for Various System Voltages

Arrester MCOV (kV)

System L-L Voltage kV

Temporarily Ungrounded, Impedance Grounded or Ungrounded Circuits

Grounded Neutral Circuits

Nominal Maximum

(1)

(2)

2.40 4.16

2.52 4.37

2.55 2.55

2.55

2.55

5.1 5.1

5.1 5.1

4.8 6.9

54

5.1 5.1 5.1

7.25 8.74 12.6 13.1 13.9 14.5 21.8 24.2 26.2 36.2 48.3 72.5 121 145 169 242 362 420 550 800 24

7.65 7.65 10.2 12.7 12.7 12.7 19.5 19.5 19.5

7.65

8.32

8.4

12

7.65 7.65

12.7 12.7 12.7 15.3

12.47

13.2 13.8

8.4 8.4

20.78 22.86

12.7 15.3 15.3 15.3

22 22 22 24 36 48 70

23

24.94

22 29 39 57 98

34.5

22 29 42 70 84 98

46 69

115 138 161 230 345 400 500 765

115 131 152 220

115 140 209

140 209 245 318 470

– – – –

– – – –

trust

Notes: (1) For normal duty. Line-to-ground fault up to 30 minutes.

(2) For severe duty. Line-to-ground fault up to 2,000 hours.

Page 8 | October 2023