Baumuller b maXX BM3400 Series - Protection of Device and Cables

Requirements to the onneting ables 6.6T
6.5 Requirements to the onneting ables
• You must consider IEC/EN 60204-1, chapter 13 at selection of connection cables.
• Use a copper cable for 60°C/75°C in case you consider UL 508 C.
Further infor mation (e.g. maximum allowable length) you will find in «Appendix D - Circuit mains - device»
from page 189 to «Appendix D - Circuit device - motor» from page 189.
6.6 Protetion of the devie and the able resp etively
In order to protect the device or the cables against damage/destruction by the mains, you must install fuses.
Data of the necessary fuses are found in «Appendix D - Fuse protection» from page 187.
Optimal protection could be reached by adding cable protection and device protection.
Cable protection should be designed primarily to protect ca ble, that means the used cable determines the
protection.
To operate b maXX® BM3400 devices it is necessary to use cable protection according to «Appendix D - Fuse
protection» from page 187.
If several devices parallely operate at the same mains supply, cable and cable protection have to be selected
to drive the sum of all peak currents of all d evices during the possible overload duration. In this case, device
protection has to be set up for each device separately.
At dimensioning of the fuses pay attention to selectivity, that means, select the fuses in a way that errors of
the device or the motor a re handled by device protection a nd errors within the switching cabinet (cables from
cable protection to device protection) lead to activation of the cable protection.
The precharge circuit of b maXX® BM3400 devices uses resistors to limit current. Devices of housing sizes 0
and 1 are equipped with NTC resistors, devices of housing size 2 use normal resistors for current limiting.
Due to heating of the resistors d uring precharge - especially at devices of housing size 0 and 1 - resistance
values drop and following the current rises temporarily.
Control of the precharge relay w hich will be activated, if an adjustable limit (P1242) is exceeded, is based on
measuring the DC link voltage. After activation of the precharge relay only the mains inductivity is effective
for current limiting.
Instrution Manual b maXX ® BM3400 57
Doument No.: 5.07013.03 from 206