Original Version
Rule 56.8 (Table 13)
56.8 Guy Insulators
Insulators which sectionalize guys shall conform to the following specifications based on the highest voltage carried at the level on the pole, tower, structure or crossarm nearest which the guy is attached and also based on the voltage of higher voltage circuits through which the guy passes.
A. Material
Insulators used in guys on supply lines shall be porcelain, glass or other suitable material.
B. Strength (see Rule 44, Table 4 and Rule 49.5-B)
C. Voltage Requirements
Insulators used in guys on supply lines shall be so designed that their dry flashover voltage is not more than 75% of their puncture voltage at operating frequencies.
Insulators used in guys on supply lines shall have a dry flashover voltage not less than as specified in Table 13 when tested in accordance with the Standards (No. 41, March 1930) of the American Institute of Electrical Engineers under the maximum mechanical loadings specified by this Order for the guy construction involved.
Table 13 Guy Insulator Flashover Voltage |
|
Nominal voltage of circuits nearest point of attachments |
Dry flashover voltage of insulators |
0-7500 volts |
15,000 volts |
7500-17,500 volts |
Double the circuit voltage |
Over 17,500 volts |
35,000 volts |
Strikeout and Underline Version
Rule 56.8 (Table 13)
56.8 Guy Insulators
Insulators which sectionalize guys shall conform to the following specifications based on the highest voltage carried at the level on the pole, tower, structure or crossarm nearest which the guy is attached and also based on the voltage of higher voltage circuits through which the guy passes.
A. Material
Insulators used in guys on supply lines shall be porcelain, glass or other suitable material.
B. Strength (see Rule 44, Table 4 and Rule 49.5-B)
C. Voltage Requirements
Insulators used in guys on supply lines shall be so designed that their dry flashover voltage is not more than 75% of their puncture voltage at operating frequencies.
Insulators used in guys on supply lines shall have a dry flashover voltage not less than as specified in Table 13 when tested in accordance with the Standards (No. 41, March 1930) of the American Institute of Electrical Engineers under the maximum mechanical loadings specified by this Order for the guy construction involved.
Table 13 Guy Insulator Flashover Voltage |
|
Nominal voltage of Is in Proximity |
Dry flashover voltage of insulators |
0-7500 volts |
15,000 volts |
7501-17,500 volts |
Double the circuit voltage |
|
35,000 volts |
22,501 – 35,500 volts |
Double the circuit voltage |
Note: To Meet dry flashover requirements, use of multiple insulators in series is permissible
Final Version
Rule 56.8 (Table 13)
56.8 Guy Insulators
Insulators which sectionalize guys shall conform to the following specifications based on the highest voltage carried at the level on the pole, tower, structure or crossarm nearest which the guy is attached and also based on the voltage of higher voltage circuits through which the guy passes.
A. Material
Insulators used in guys on supply lines shall be porcelain, glass or other suitable material.
B. Strength (see Rule 44, Table 4 and Rule 49.5-B)
C. Voltage Requirements
Insulators used in guys on supply lines shall be so designed that their dry flashover voltage is not more than 75% of their puncture voltage at operating frequencies.
Insulators used in guys on supply lines shall have a dry flashover voltage not less than as specified in Table 13 when tested in accordance with the Standards (No. 41, March 1930) of the American Institute of Electrical Engineers under the maximum mechanical loadings specified by this Order for the guy construction involved.
Table 13 Guy Insulator Flashover Voltage |
|
Nominal voltage of Circuit to Which Guy Is in Proximity |
Dry flashover voltage of insulators |
0-7500 volts |
15,000 volts |
7501-17,500 volts |
Double the circuit voltage |
17,501 – 22,500 volts |
35,000 volts |
22,501 – 35,500 volts |
Double the circuit voltage |
Note: To Meet dry flashover requirements, use of multiple insulators in series is permissible