Connection Of A Braking Resistor; Braking Resistor Without Temperature Monitoring - KEB COMBIVERT F5 Instruction Manual

Connection Power Unit
2.7.5

Connection of a braking resistor

2.7.5.1 Braking resistor without temperature monitoring

Intrinsically safe braking resistor without temperature monitoring
Braking resistors dissipate the produced energy of the motor into heat during
generatoric operation. Thus braking resistors can cause very high surface tem-
peratures. During assembly pay attention to appropriate protection against con-
tact and fire.
The use of a regenerative unit is reasonable for applications which produce a lot
of regenerative energy. Regeneration of excess energy into the mains.
The mains voltage must always be switched off in order to guarantee fire protec-
tion in case of a defective braking transistor.
The frequency inverter remains in operation in spite of switched off power sup-
ply in generatoric operation. An error must be released by external wiring which
switches the modulation off in the inverter. This can occur e.g. at terminals T1/
T2 or via digital input. The frequency inverter must be programmed accordingly
in each case.
The response threshold of the braking transistsor (Pn.69) for all other controls
without safety technology (A, E, G, H, M) must be adjusted at least to 770 Vdc
(see annex D).
R
B
Only "intrinsically safe" braking resistors are permissible for operation without
temperature monitoring.
+PA
G1
PB
GB - 29