IEC 60898-2-2003 pdf free download – Circuit-breakers for overcurrent protection for household and similar installations – Part 2: Circuit-breakers for a.c. and d.c. operation.
1 scope and object
This clause of Part 1 is applicable except as follows:
Addition at the end of the first paragraph:
This standard gives additional requirements for single- and two-pole circuit-breakers which, inaddition to the above characteristics, are suitable for operation with direct current, and have arated d.c. voltage not exceeding 220 V for single-pole and 440 V for two-pole circuit-breakers,a rated current not exceeding 125 A and a rated d.c. short-circuit capacity not exceeding10 000 A.
NOTE This standard applies to circuit-breakers able to make and break both a.c. current and d.c. current.Delete the last two paragraphs.
2Normative referencesThis clause of Part 1 applies.
Delete lEC 61009-1:1991,IEC 61009-2-1:1991 and lEC 61009-2-2:1991.
3Definitions
Clause 3 of Part 1 applies with the following modification:Addition:
3.5.10.3
time constant
the rise time T = L/R(ms) of a prospective direct current to reach a value of 0,63 times themaximum peak current
4 Classification
Clause 4 of Part 1 applies with the following modifications:
4.1 According to the number of poles
Replacement:
– single-pole circuit-breakers;
– two-pole circuit-breakers with two protected poles.
4.5 According to the instantaneous tripping current (see 3.5.1 7)
Delete D-Type.
Addition:
4.7 According to the time constant
– Circuit-breakers suitable for d.c. circuits with a time constant of T ≤ 4 ms.
– Circuit-breakers suitable for d.c. circuits with a time constant of T ≤ 1 5 ms.
NOTE It is assumed that short-circuit currents of 1 500 A are not exceeded in installations in which, due to the loads connected, time constants in normal service up to 1 5 ms can occur. Where higher short-circuit currents may occur, the time constant of T = 4 ms is considered sufficient.
5 Characteristics of circuit-breakers
Clause 5 applies with the following modification:
5.3.1 Preferred values of rated voltage
Replacement:
The preferred values of rated voltages are given in table 1 .
Examples of connections of circuit-breakers in d.c. systems are given in figure 1 8.
The manufacturer shall declare in his literature the minimum voltage for which the circuitreaker is designed.
Relevant tests are under consideration.
6 Marking and other product information
Clause 6 of Part 1 applies with the following modifications:Replacement:
c) rated a.c. voltage with the symbol ~ and rated d.c. voltage with the symbol —d) replace(B, C or D) by (B or C).
f) rated short-circuit capacity for a.c. and d.c. in amperes in one rectangle，without the
symbol A， if valid for both a.c. and d.c.(see example 1 below). If the rated short-circuitcapacity is different for a.c. and d.c. this shall be indicated in two adjacent rectangles,without the symbol A，with the symbol ~ near the rectangle containing the a.c. value andwith the symbol –near the rectangle containing the d.c. value (see example 2 below).Addition:
l) time constant T15 within a rectangle，if applicable,associated with the marking for the
short-circuit capacity at the time constant of 15 ms (see example 3 below).
Replacement of the first paragraph following l):
lf， for small devices， the space available does not allow all the above data to be marked， atleast the information under c) and d) shall be marked and visible when the circuit-breaker isinstalled.
The information under a), b),e), f). g), h), i) and l) may be marked on the side or on the backof the device and be visible only before the device is installed.
Alternatively，the information under g) may be on the inside of any cover which has to beremoved in order to connect the supply wires.Any remaining information not marked shallbe given in the manufacturer’s literature.IEC 60898-2 pdf download.