4�3�- Cabling Cross Sections And Protections - Circutor computer MAX 6 Instruction Manual

it measures the total current of all the loads, including also the compensation capacitor bank
(see
Figure 3
The CT should be installed preferably in phase L1, while the voltage measuring terminals of
Computer MAX should be connected to phases L2 and L3 (see schematics in
). It's important to respect the connection senses of P1-P2 and S1-S2 shown in the above
ure 5
mentioned figs, otherwise the phase difference will have to be corrected by adjusting the device
according to set-up procedure indicated in
RIGHT CONNECTION
The CT measures the whole
current of loads + capacitor
bank.
In case of malfunction check
that the CT is not shortcircuited
4.3.- CABLING CROSS SECTIONS AND PROTECTIONS
The supply circuit must be protected by means of fuses or a circuit breaker sized between 0,5
and 2 A.
Recommended fuses are gl type (IEC 269) or M type (IEC 127). A main circuit breaker must be
provided in order to allow the disconnection of control circuits from supply (Computer, relays,
contactor coils, etc.)
The main switch must be easily accessible. The cabling cross section must be minimum 1,5
mm for the voltage supply and for the relay outputs and 2,5 mm
2
secondary of CT to computer MAX. For distances between CT and computer higher than 10m
the cross section of the last must be increased at a rate of 1 extra mm
12
)
If CT is placed in this position,
NONE of the CAPACITOR STAGES
WILL CONNECT.
The equipment does not regulate
properly�
Figure 3:Placement of current transformer (CT)
"6.1.8.- U, I PHASE ANGLE SETTING.".
WRONG CONNECTION
If CT is placed in this position ALL
THE CAPACITOR STAGES WILL
CONNECT.
WARNING! This situation may
cause overcompensation, reso-
nance and overcurrent
computer MAX
and
Figure 4
for the cables connecting
2
every 10 m.
2
Instruction Manual
Fig-