Phase Failure; Earth Fault Monitoring - Eaton ZEV Handbuch

Motor-protective system ZEV
46

Phase failure

In the event of a phase failure, i.e. with an imbalance of
f 50 %, the unit is tripped within a delay time of
2.5 seconds g20 %.

Earth fault monitoring

In addition to standard motor-protective functions, such as
the protection from overload or phase failure and imbalance,
the device is also equipped with a thermistor input for direct
temperature monitoring and with the option of monitoring
earth faults via an auxiliary core-balance transformers.
Table 4: Core-balance transformers for earth fault monitoring
Core-balance Opening
transformer diameter
mm
SSW40-0,3 40
SSW40-0,5 40
SSW40-1 40
SSW65-0,5 65
SSW65-1 65
SSW120-0,5 120
SSW120-1 120
Caution!
An earth fault does not lead to a changeover of the
contacts 95-96 and 97-98.
In addition to the message shown on the display of the ZEV
(a fig. 30 on Page 63), the "earth fault" signal can also be
used to switch over one of the contacts 05-06 or 07-08
(a fig. 7 on Page 50).
05/11 MN03407008Z-DE/EN
Fault current
A
0.3
0.5
1
0.5
1
0.5
1