6KBU300
—————— TECHNICAL DATA —————— 3
7
The max. lenght of the connections between braking units and inverters must not exceed two meters, (the
twisted connection with the appropriate wire section, is always supplied together with the braking unit).
For the parallel connection of braking units, the user must always use a twisted cable; the units should however
be mounted side by side and the connections between terminals C and D should be kept as short as possible.
The power fuses of the correspondent inverters must be super fast.
3.5. OVERTEMPERATURE ALARM.
When the braking resistor reaches too high temperature, there is the possibility to trip out the braking unit. This
happen by means of the thermal relay (Klixon), and connecting its contact (normally closed) between the output
+24V (terminal 1) and the input protection TIM (terminal 3).
The contact of the thermal relay can be also externally supplied with a voltage between 15 and 30V whose 0V
potential must be connected to the 0V24V (terminal 2).
When there is the intervention of the thermal relay (opening of the contact) the braking unit is immediately tripped
, the red led AL lights on and the OK relay contact opens (terminals 75 76).
When an Overtemperature alarm occurs due to an overheating of the power module’s heatsink (opening of the
relative thermal relay), a BU trip occurs.
Once the alarm has been eliminated, it is possible to reset the braking unit using one of these modalities:
- through button S3
- through remote command inserted on the terminal 4
- removing BU from DC BUS
The diagrams in the following pictures show a typical connection for protection with an external contact for the
alarm reset.
Tothe inverter
5
C
6
DBR
3
1
4
R
10
9Alarmreset
78
PE
CR 56
CR
C
DBR
PE
78910
3
2
4
Alarmreset
0V
R
15…30Vdc
Tothe inverter
Using the internal power supply of the braking unit Using external power supply from the unit