Bl This standard establishes the construction characteristics and operating conditions to which fast-type fuses, with screw-in cartridge holders, suitable for voltages no greater than 500 V, for direct and alternating current, must respond. B-2 This standard does not include fuses intended for use in explosive environments or with corrosive gases, nor in on-board installations.
IRAM 2121-1958 history
1958IRAM 2121-1958 Fast-acting fuses with portable spiral coils for voltages up to and including 500 volts