238 Resistor braking
Planning the braking system
Verifying the capacity of the braking equipment
1. Calculate the maximum power generated by the motor during braking (
P
max
).
2. Ensure that the braking power of the chopper is equal to or greater than
P
max
.
The
P
brmax
values specified in the ratings table on page
are for the reference
braking cycle (1 minute of braking, 9 minutes of rest). If the actual duty cycle does not
correspond to the reference cycle, the maximum allowed braking power (
P
br
) must be
used instead. In the ratings table,
P
br
is given for two additional braking cycles. See
below for instructions on calculating
P
br
for other braking cycles.
3. Check the resistor selection. The energy generated by the motor during a 400-second
period must not exceed the heat dissipation capacity of the resistor (
E
R
).
If the
E
R
of the resistor is not sufficient, it is possible to use a four-resistor assembly in
which two resistors are connected in parallel, two in series. The
E
R
value of the four-
resistor assembly is four times that of a single resistor.
Custom resistors
Resistors other than those available as D151 can be used provided that
•
the resistance is not lower than the value given in the ratings table (page
)
WARNING!
Never use a brake resistor with a resistance below the value specified
for the particular drive / brake chopper / resistor combination. The drive and the
chopper would not able to handle the overcurrent caused by the low resistance.
•
the resistance of the custom resistor does not restrict the braking capacity needed, ie.
where
•
the heat dissipation capacity
E
R
of the resistor is sufficient for the application (see step
3 above).
P
max
Maximum power generated by the motor during braking
U
DC
Voltage over the resistor during braking.
U
DC
equals
1.35 · 1.25 · 415 V DC (when supply voltage is 380 to 415 V AC)
1.35 · 1.25 · 500 V DC (when supply voltage is 440 to 500 V AC) or
1.35 · 1.25 · 690 V DC (when supply voltage is 525 to 690 AC)
R
Resistor resistance (ohm)
P
max
<
U
DC
R
2
Summary of Contents for ACS880-17
Page 1: ...ABB industrial drives Hardware manual ACS880 37 drives ...
Page 3: ......
Page 4: ......
Page 6: ......
Page 16: ...16 ...
Page 30: ...30 Introduction to the manual ...
Page 70: ...70 Mechanical installation ...
Page 105: ...Electrical installation 105 4 5 3 6 7 ...
Page 107: ...Electrical installation 107 5 6 4 3 ...
Page 108: ...108 Electrical installation 7 8 8 ...
Page 109: ...Electrical installation 109 9 10 ...
Page 111: ...Electrical installation 111 2 360 grounding detail a b b 1 5 a 11 b a PE 10 7 5 6 8 ...
Page 117: ...Electrical installation 117 PE 11 8 4 9 11 ...
Page 134: ...134 Control units of the drive ...
Page 140: ...140 Start up ...
Page 142: ...142 Fault tracing ...
Page 154: ...154 Maintenance 4 5 6 7 8 6 10 10 ...
Page 162: ...162 Maintenance 5 6 3 4 7 ...
Page 163: ...Maintenance 163 6 8 7 11 10 9 ...
Page 167: ...Maintenance 167 3 4b 4a 4b 8 ...
Page 185: ...Technical data 185 Declaration of Conformity ...
Page 186: ...186 Technical data ...
Page 196: ...196 Dimensions Dimension drawing examples Frame 1 R8i 1 R8i ...
Page 197: ...Dimensions 197 Frame 1 R8i 1 R8i top cable entry exit H351 H353 ...
Page 198: ...198 Dimensions Frame 1 R8i 1 R8i with brake choppers and resistors D150 D151 ...
Page 199: ...Dimensions 199 Frame 1 R8i 1 R8i with sine output filter E206 ...
Page 200: ...200 Dimensions Frame 2 R8i 2 R8i eg ACS880 37 1110A 3 IP22 ...
Page 201: ...Dimensions 201 Frame 2 R8i 2 R8i eg ACS880 37 1210A 3 IP54 ...
Page 204: ...204 Dimensions Frame 2 R8i 2 R8i with main breaker F255 and top entry top exit H351 H353 1 2 ...
Page 205: ...Dimensions 205 Frame 2 R8i 2 R8i with main breaker F255 and top entry top exit H351 H353 2 2 ...
Page 206: ...206 Dimensions Frame 3 R8i 3 R8i 1 2 ...
Page 207: ...Dimensions 207 Frame 3 R8i 3 R8i 2 2 ...
Page 208: ...208 Dimensions Frame 3 R8i 3 R8i with common motor terminal cubicle H359 1 2 ...
Page 209: ...Dimensions 209 Frame 3 R8i 3 R8i with common motor terminal cubicle H359 2 2 ...
Page 217: ...Dimensions 217 Sine filter E206 cubicle 1000 mm top cable exit ...
Page 221: ...Dimensions 221 Cubicle width 400 mm top cable exit Cubicle width 600 mm bottom cable exit ...
Page 222: ...222 Dimensions Cubicle width 600 mm top cable exit ...
Page 234: ...234 The Safe torque off function ...
Page 244: ...www abb com drives www abb com drivespartners 3AXD50000020437 Rev A EN 2015 02 06 Contact us ...