CABLE TYPE CURRENT TRANSFORMERS
Application
KAT and SAA cable type transformers;
are used for metering and protection purposes. Max.operating voltage is 0.72 kV.
They can be used with fully insulated cables on all voltage level.
Secondary terminals
One of the secondary terminals should be earthed for safety.
Secondary circuit of a current transformer must not be operated with an open circuit.
It should be connected measuring devices before application of primary connection as seen in figure-1.
The secondary winding of current transformer which will not be used must always be short-circuited and earthed as seen in figure-2.
For the transformer with reconnectable and/or tapped secondaries, unused terminals must be left open as seen in figure 3.
Assembly
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Cable type current transformers (KAT) and split core type current transformers (SAA) have a base plate that allows mounting in any position. Those are maintenance-free products on the operation. If cable type current transformers will be assembled on to isolated HV cable, shielded cable should be earthed as seen on figure-4 to be able to prevent effects caused by the possible leakage current flow on measuring systems. |
Technical Data
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SPLIT CORE CABLE TYPE CURRENT TRANSFORMERS
Split Core Current Transformers have a magnetic circuit which is splitted two parts and its max. operating votage is 0.72 kV with non-insulated busbars.
However they can be used with fully insulated cables on all voltage level. These transformers can be assembled to the system without
any power interruption and without the need of demounting any conductor. These transformers are used for measuring and protection. Moreover;
they are used for special applications such as measurement of leakage current with precision cores which have high magnetic permeability.
SAA For Measuring Earth Leakage
Nominal Current : 50A - 100A.
SAA For Measuring Earth Leakage transformers have high permeability cores. They are suitable for measuring earth leakage current at
three phase networks.
At well designed three phase network, any of three phase current’s vectorial sum is zero.
In case of an earth leakage the balance of the current in cable is distrupted and the resultant earth leakage current excites the transformer.
Depending on the measurement procedure of the earth fault
currents, either a secondary current or a voltage transformer simply actuates earth fault detectors and/or relays
Technical Data
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