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1 ZB12-…/XTOB…BC1 and ZB32-…/XTOB…CC1 overload relays
1.3 Description of device
ZB12-…, ZB32-…
11/16 MN03407004Z-DE/EN
www.eaton.com
31
Table 4: Current ranges of ZB32-…/XTOB…CC1 relays
1.3.3 Temperature compensation
Two parameters influence the deflection of the bimetallic releases. There is
for one the heat which is generated in proportion to the current flow, and
secondly, the influence of the ambient air temperature.
The influence of the ambient air temperature is automatically compensated
within a temperature range from -5 °C to +55 °C by means of an additional
current-free bimetallic release that continuously corrects the tripping range.
1.3.4 Phase failure
The ZB12-…/XTOB…BC1 and ZB32-…/XTOB…CC1 overload relays are
phase failure sensitive. The deflecting action of all three bimetallic releases is
directed towards a tripping bridge that switches over a snap-action switch
when the limit value is reached. At the same time, all three bimetallic
releases shift the differential bridge.
If the path of action of one of the bimetallic releases is reduced due to a
phase loss, the differential bridge is retarded and the distance is converted
into an additional tripping distance, which leads to an early tripping.
Type
Current range I
ZB32-…
XTOB…
A
ZB32-0,16
XTOBP16CC1
0.1 - 0.16
ZB32-0,24
XTOBP24CC1
0.16 - 0.24
ZB32-0,4
XTOBP40CC1
0.24 - 0.4
ZB32-0,6
XTOBP60CC1
0.4 - 0.6
ZB32-1,0
XTOB001CC1
0.6 - 1.0
ZB32-1,6
XTOB1P6CC1
1.0 - 1.6
ZB32-2,4
XTOB2P4CC1
1.6 - 2.4
ZB32-4
XTOB004CC1
2.4 - 4.0
ZB32-6
XTOB006CC1
4.0 - 6.0
ZB32-10
XTOB010CC1
6.0 - 10
ZB32-16
XTOB016CC1
10 - 16
ZB32-24
XTOB024CC1
16 - 24
ZB32-32
XTOB032CC1
24 - 32
ZB32-38
XTOB038CC1
32 - 38