(Sub) CLAUSE/ANNEX HEADING:
OTHER RELEVANT (Sub) CLAUSES/ANNEXES (as applicable):
DESCRIPTION OF ISSUE:
Clarification of the meaning of the second paragraph of Clause 4.3 that reads:
Circuits, or parts of a circuit supplied with an open circuit voltage not exceeding 35V (peak) ac or dc and not generating voltages above that value, are not considered to present a fire hazard if the circuit which may be drawn from the supplying circuit for more than 2 min at any load, including short circuit, is limited to not more than 0.2 A. Such supplied circuits are not subject to fault condition testing.
The above clause states that a circuit fire hazard is considered to exist if either the voltage is greater than 35 volts or the current is greater than 0.2 amperes. See table below.
Should fault testing be conducted?
> 35 volts < or = 35 volts
> 0.2 amps Yes Yes
< or = 0.2 amps Yes No
The words are written in a manner that can be misinterpreted to suggest that both 35 V and 0.2A are required. However, the wording is in reverse of standard requirement style. That is, the requirement indicates when a fire hazard is NOT considered to be present instead of when it IS considered to be present.
SEE RELATED PAG: