Technosoft iPOS4808 MX Series, Technical Reference

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
Technosoft 2014 64 iPOS4808 MX Technical Reference
The brake resistor value must be chosen to respect the following conditions:
1. to limit the maximum current below the drive peak current I
PEAK
= 10A
PEAK
MAX
BR
I
U
R

2. to sustain the required braking power :
d
brake MAX
M
BR
t
) U U ( C E
P
2 2
2
1
 

where C is the capacitance on the motor supply (external), i.e:
BR
BRAKE
BR
P
U
R


2
2
3. to limit the average current below the drive nominal current I
NOM
=4A
2
NOM
CYCLE
d BR
BR
I t
t P
R



where t
CYCLE
is the time interval between 2 brakes in case of repetitive moves.
4. to be rated for an average power
CY CLE
d BR
AV
t
t P
P


and a peak power
BR
MAX
PEAK
R
U
P
2

Remarks:
1. If
BR
BRAKE
PEAK
MAX
P
U
I
U


2
2
the braking power P
BR
must be reduced by increasing either t
d
–
the
time to decelerate or C
–
the external capacitor on the motor supply
2. If
BR
BRAKE
NOM
CY CLE
d BR
P
U
I t
t P




2
2
2
either the braking power must be reduced (see Remark 1)
or t
CYCLE
–
the time interval between braking cycles must be increased
WARNING!
THE BRAKE RESISTOR MAY HAVE HOT SURFACES
DURING OPERATION.