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861-9601.9 • INSTALLATION AND OPERATING INSTRUCTIONS • 8DA10 • Revision 11
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Description
10
Current and voltage transformers
10.1
4MT and 4MU voltage transformers
Features
• According to IEC 61869-3
• Cast-resin insulated
• Inductive type
• Safe-to-touch due to metal enclosure
Mounting locations
• On the busbar
• At the panel connection housing
Electrical data
Fig. 7:
Voltage transformer installation (basic scheme)
①
Busbar voltage transformer 4MT3
③
Voltage transformer 4MU4 with
three-position disconnector
②
Feeder voltage transformer 4MT7
(connection at panel connection housing)
④
Feeder voltage transformer 4MU3
(not in the panel, connection via flexible
cable with plug size S2 at the panel
connection housing, and metal-enclosed
voltage transformer)
Mounting locations
Type
Remark
Busbar
4MT3
optionally with three-position
disconnector
4MU4
Panel connection housing 4MU3
external
4MT7
directly plugged in
Designation
4MT3
4MU4
4MT7
4MU3
Operating voltage kV
3.3 to 23.0
24.0 to 38.0
3.3 to 38.0
3.3 to 38.0
Rated voltage kV
24.0
40.5
40.5
40.5
Rated short-duration power-frequency
withstand voltage kV
65.0
95.0
95.0
95.0
Rated lightning impulse withstand voltage
kV
125.0
200.0
200.0
200.0
Rated voltage factor
Un / 8h = 1.9
Un / 8h = 1.9
Un / 8h = 1.9
Un / 8h = 1.9
Un / continuous = 1.2
Un / continuous = 1.2
Un / continuous = 1.2
Un / continuous = 1.2
Standard
IEC
IEC
IEC
IEC
GOST
GOST
GOST
GOST
GB
GB
GB
GB