LOW HARMONIC REGENERATIVE CABINET DRIVE
vacon • 51
Figure 7-4. Circuit diagram of remote contacts for the control of the
MCCB and pre-charging circuit (NXC regenerative low-harmonic FR12)
In case of a voltage drop of <0.7xU
N
or a blackout in the supplying network, the undervoltage release coil
will open the circuit-breaker and pre-charging and MCCB closing has to be activated by the remote
charging pulse when the supply is energized.
7.1.3
Automatic operation (AUTO)
The pre-charging and closing of the circuit-breaker is automatically done when the
REM-MAN-AUTO
selector switch is in
AUTO
position and the supply voltage is energized. The pre-charging of the units will
automatically (directly) start when the control switch -S6 is turned into
Auto
position. The AFE unit will
automatically close the circuit-breakers after DC voltage has reached a certain level and the AFE READY
LED will illuminate.
The unit will re-charge automatically and close the circuit-breakers if the main supply voltage has been
cut and turned back on (e.g. voltage drop in the network). The 0-1-Start switch has to be in position
1
which
enables automatic function.
Turning the switch –S10 to position
0
will open the circuit-breaker even if the
REM-MAN-AUTO
selector
switch is in
AUTO
position.
7.1.4
Circuit-Breaker TRIP due to overload or short-circuit
The electronic trip unit will open/trip the circuit-breaker in case of an overload or short circuit. The trip
indication contacts of circuit-breakers are connected in series and if one of the circuit-breakers trips due
to an overload or short circuit current, it will automatically open/trip the other circuit-breakers. The
MCCB
FAULT LED
will illuminate and indicate that the circuit breakers are in tripped state.
Figure 7-5. MCCB FAULT indicator
Clearwater Tech - Phone: 800.894.0412 - Fax: 208.368.0415 - Web: www.clrwtr.com - Email: [email protected]
