Mitsubishi Electric C Series Handling And Maintenance page 27

1 1 1 Cautionary instructions for using heat resistive wire
1 1
For using insulated wires of higher heat resistance than that of 600 V PVC insulated wire (allowable
temperature 60°C), it is necessary to take the following points into consideration.
For circuit breakers, size of test wire is stipulated by each test current in IEC60947-1
If size of connection wire is thinner than the test wire size, temperature of the breaker terminals
increases and overcurrent tripping operation characteristic may change in some cases. (Operating
time becomes shorter usually.) At motor load, for example, influence of change in operation charac-
teristic by difference in size of connection wire is insignificant and can be disregarded because the
load current is far lower than the rated current of the circuit breaker.
Size of test wire
Range of test current
(A)
0 <
8
12
15
20
25
32
50
65
85
100
115
130
150
175
200
225
250
275
300
350
(2) Maximum operating current of installation without clearance between breakers
In case of installation without clearance between breakers, because maifunction failures can result
by heat of breaker, use the operating current not to exceed the below value.
BH BH-P BH-S
CP30-BA CP-B CP-S
NF30-CS MB30-CS
NF32-SW NF63-CW MB30-SW
MB50-SW
NF63-SW NF63-HW
MB50-SW
NF125-CW
NF125-SW NF125-SGW MB100-SW
NF125-HW NF125-HGW
NF160-SGW NF160-HGW
NF250-CW
NF250-SW NF250-SGW MB225-SW
NF250-HW NF250-HGW
NF400-CW NF400-SW NF400-SEW NF400-HEW NV400-CW NV400-SW NV400-SEW NV400-HEW
NF400-REWNF400-UEW
NF630-CW NF630-SW NF630-SEW NF630-HEW NV630-CW NV630-SW NV630-SEW NV630-HEW
NF630-REW
NF800-CEWNF800-SDW NF800-SEW NF800-HEW NV800-SEW NV800-HEW
NF800-REWNF800-UEW
25
Conductor size
2
(mm
≤
8 1.0
12 1.5
15 2.5
20 2.5
25 4.0
32 6.0
50 10
65 16
85 25
35
100
35
115
130 50
115 50
175 70
200 95
225 95
250 120
275 150
300 185
350 185
240
400
Type name of breaker
BH-PS
NV30-CS
NV63-SW
NV63-SW
NV125-CW
NV125-SW NV100-SEP
NV125-HW NV100-HEP
NV250-CW
NV250-SW NV250-SEW
NV250-HW NV250-HEW
NV400-REW
2 2 Connection of aluminum conductors 2 2 2
• When aluminum conductors are connected, be careful to
)
prevent the contact resistance (due to the oxidized film of
aluminum) from being increased.
• The surface of the connection point of the aluminum con-
ductors shall be properly treated by plating (zinc displace-
ment-Copper-Silver) or by joint compound. If the treatment
is done only by joint compound, reliability is low, this should
be limited to when plating is impossible (eg. at site).
• For aluminum cables, use compression terminals that are
exclusively for aluminum cables.
• The compression portion of the terminal shall be provided
with taping, and the aluminum wire shall not be exposed to
the atmosphere.
Circuit breaker
NV50-CSA MB30-CS
NV63-CW
NV63-HW
Taping
Aluminum cable
Compression terminal for
aluminum cable
Maximum operating current
80% of rated current
90% of rated current