Current transformer (ct) connection – CIRCUTOR OPTIM HYB Series User Manual

Page 20

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3.9.- CURRENT TRANSFORMER (CT) CONNECTION

For standard units that come with a CVM-MINI-RS485 power analyzer: You

must place 3 current transformers (CT) outside the capacitor bank, one at

each phase, measuring the total current of the load plus the capacitor bank

itself (

Figure 11

).

The standard transformer must have a nominal output of 5 A at the secondary.

For correct measurement of powers and angles, you must connect the CT to

each phase with the direction of the current from P1 to P2 (

Figure 11

) and connect

the secondary (terminals S1, S2) to the terminals with the same name on the ca-

pacitor bank (see

Figure 11

and

Figure 12

).

Avoid the flow of current through the CT's primary before connecting the second-

ary to the S1 and S2 terminals of the capacitor bank.

If the CT must be installed while the installation is under load, short-circuit S1 and

S2 while they are not connected to the capacitor bank.

The current value of the CT primary winding must be equal to or slightly greater than the size of

the mains switch of the installation. Therefore, the CT must be able to measure the maximum

current expected to be consumed by all the loads being compensated.

L1
L2
L3
N

RED

CARGA

3x400 V / 1x230 V - 50 Hz

L1
L2

L3

S1

N

TB1

BATERÍA DE
CONDENSADORES

1S1 1S2

S1

S2

S1

S2

S1

S2

T.I.1

T.I.2

T.I.3

2S1 2S2

3S1 3S2

Figure 11: Installation of external current transformers (CT).

The connection point of the CT for a capacitor bank that compensates an entire installation is

after the mains switch of the installation.

To prevent excessive attenuation of the signal, it is recommended that the minimum secondary

section winding cable size (terminals S1, S2) is at least

2.5 mm

2

.

20

OPTIM HYB Series

Instruction Manual

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