Lenze ERBGxxxxxxxx - Manual (Page 41)

Product description
Dimensioning conditions
3
l
41 EDKRBG018R DE/EN/FR/ES/IT 8.0
3.4 Dimensioning conditions
If brake resistors are used, observe the following:
ƒ Mean value of regenerative power < permanent power P
d
of the brake
resistor.
ƒ Regenerative power during braking time < heat quantity Q
B
of the brake
resistor.
ƒ Braking time < 10 % of cycle time (braking time + dead time).
ƒ Always connect the thermal contact and integrate it in a way into the
system monitoring that the mains supply will be switched off when the
standard device is overheated.
At all times, the following must apply: In the time interval t
cyc,RB
(brake resistor
cycle) the cumulative braking times t
brk
must always be £ of the maximum total
braking time t
brk,max
.
Calculation
Brake resistor cycle t
cyc,RB
:
t
cyc,RB
+ Q B
P
d
with
Q B Heat quantity in Ws
P d Permanent power in W
Max. total braking time t
brk,max
within the time interval t
cyc,RB
:
t
brk,max
+ Q B
@ R
B
U
max
2
with
Q B Heat quantity in Ws
R B Resistance in W
U
max
Max. operating voltage in V