UL 98:2006 pdf download – Enclosed and Dead- Front Switches.
9.2.9 The marking of a switch shall be considered to be acceptable it located on the inside of a hinged door, provided the door may be opened regardless of the position of the switch.
9.2.10 A switch rated at more than 1 200 A at 250 V or less and a switch rated at more than 600 A at
more than 250 V shall be conspicuously marked on the outside of the enclosure, For isolating u-se only
— Do not open under load”, and shall not be marked to indicate acceptability for use as service equipment.
This requirement does not apply to a switch that was found to perform acceptably in an overload test at
150 percent of rated current and In an endurance test at rated current, In accordance with 7.3.1 and 7.4.1.
9.2.11 A switch shall be marked plainly on the outside of the enclosure to indicate the on, off, and any other positions of the switch.
9.2.12 A switch intended to accept Class K. Class H. or plug fuses shall be marked, Suitable for use on a circuit capable of delivering not more than 10 000 amperes. rms syniinetrical, – volts maximUm” or the equivalent.
9.2.12.1 A fused switch intended for field conversion shall be marked as indicated in 9.2.15.
9.2.13 An untused switch shall be marked. “This switch is suitable for use on a circuit capable of delrvenng not more than ______ amperes, rms symmetrical, when protected by ______ fuses (Type circuit breaker) rated ______ amperes maximum” or with an equivalent marking. See 8.5.
9.2.13.2 lIthe short-circuit current rating is 10 000 A, the Class of fuse may be omitted, but the current rating shall be provided.
9.2.13.2.1 The marking may be repeated for several different types of protection.
9.2.13.3 If the short-circuit current rating is 5 000. 7 500, or 10 000 A and the continuous current rating of the circuit breaker does not exceed that of the switch, the omission of the type designation and manufacturer of the circuit beaker shall be permitted.
9.2.13.4 If the short-circuit current rating is 5 000, 7 500, or 10 000 A and the continuous current rating of the circuit breaker exceeds that of the switch and the switch was tested for three cycles as Indicated in 7.7.4, the mission of the type designation and manutacturer of the circuit breaker shall be permitted.
9.2.13.5 If the tests mentioned In 7.7 and 7.9 are conducted with the overcurrent protection means on the line side of the unfused switch, the marking shall also specify that the fuses (or circuit breakers) shall be installed ahead of the switch.
9.2.15 A switch constructed to accept Class H or K fuses but field-convertible to accept Class C,J, R, or
T fuses, shall be marked as ollows:
a) When used with Class K or H fuses, “Suitable for use on a circuit capable of delivering not
more than 10 000 amperes, rms symmetrical,
volts, maximum.
b) When used with Class J (or T) fuses, “(When used with Class R fuses and fuse clip
assembly No.____ properly installed,) This switch is suitable for use on a circuit capable of
delivering not more than
amperes, rms symmetrical,
volts maximum,” or
equivalent wording.
c) The switch shall be marked as follows to indicate that the short-circuit current rating is only applicable when Class J (T or R) fuses are used: “Danger – Unless ClassJ (T or R) fuses are
used, this switch may present a risk of fire and injury to persons if nstalled on circuits capable
of delivering more than 10 000 amperes, rms symmetrical,” or equivalent wording. See 8.5.
9.2.16 A switch intended to accept Class J fuses by repositioning load fuse base or fuse clip assemblies shall be provided with explicit instructions for repositioning the load base fuseholder or fuse clips and associated barriers so that it will accept Class J fuses.
9.2.17 A switch intended for replacing or adding partis shall be provided with explicit instructions for ordering the required components in order to accomplish one of the ollowing:
a) Replacing the load side fuseholder or fuse cdip assembles so that it will accept only Class R
fuses,
b) Adding the load side fuseholder or fuse cdip assemblies so that it will accept either Class H, Class J or only Class R fuses,
C) Adding the rejection means to the fuse clip assemblies so that it will accept only Class R
fuses, on
d) Adding bus bars or equivalent assemblies so it will accept only Class T or C fuses.
9.2.18 The marking referred to in 9.2.15 – 9.2.17 shall be provided as a permanent part of the switch and shall be visible when the fuseholders are arranged to accept a Class H fuse or Class L fuse, as appropriate.