Chapter 4 Characteristics
4–6
4-2-2 Coasting amount
The motor coasting amount when stopped by a dynamic brake can be approximated using the following
expression.
L
MAX
=
F
G0
×
10
3
60
×
te + ( 1 +
J
L
J
M
)
×
1.1
×
(A
×
N
2
+ B)
L
MAX
: Machine coasting amount
(mm)
F
G0
: Feedrate (Rapid traverse)
(m/min)
N
: Motor speed (speed at rapid traverse)
(r/min)
J
M
: Motor inertia
(kgf•cm•sec
2
)
J
L
: Motor shaft conversion load inertia
(kgf•cm•sec
2
)
te
: Brake drive relay delay time (Normally, 0.03sec) (sec)
A
: Coefficient A (Refer to the table below)
B
: Coefficient B (Refer to the table below)
Fig. 4-3 Dynamic brake braking diagram
Table 4-3 Coasting amount calculation coefficients
Motor type
J
M
(kgf•cm•sec
2
)
A
B
Motor type
J
M
(kgf•cm•sec
2
)
A
B
HC52 (Note 1) 0.0067
9.57
×
10
−
9
7.09
×
10
−
3
HC53 (Note 1) 0.0067
9.49
×
10
−
9
6.37
×
10
−
3
HC52 (Note 2) 0.0067
3.59
×
10
−
9
4.79
×
10
−
3
HC53 (Note 2) 0.0067
2.56
×
10
−
9
6.09
×
10
−
3
HC102
0.014
2.47
×
10
−
9
5.69
×
10
−
3
HC103
0.014
1.95
×
10
−
9
6.98
×
10
−
3
HC152
0.02
1.76
×
10
−
9
5.89
×
10
−
3
HC153
0.02
1.28
×
10
−
9
9.13
×
10
−
3
HC202
0.043
15.20
×
10
−
9
9.56
×
10
−
3
HC203
0.043
9.77
×
10
−
9
60.90
×
10
−
3
HC352
0.084
8.74
×
10
−
9
13.02
×
10
−
3
HC353
0.084
4.97
×
10
−
9
24.23
×
10
−
3
HC452
0.123
2.80
×
10
−
9
19.26
×
10
−
3
HC453
0.123
2.44
×
10
−
9
32.87
×
10
−
3
HC702
0.163
13.30
×
10
−
9
6.82
×
10
−
3
HC703
0.163
1.58
×
10
−
9
36.65
×
10
−
3
HC902
0.208
2.07
×
10
−
9
26.52
×
10
−
3
HC103R
0.0015
1.24
×
10
−
9
1.22
×
10
−
3
HC153R
0.0019
0.95
×
10
−
9
1.20
×
10
−
3
HC203R
0.0023
0.59
×
10
−
9
1.61
×
10
−
3
HC353R
0.0085
1.18
×
10
−
9
5.19
×
10
−
3
HC503R
0.0122
0.96
×
10
−
9
5.64
×
10
−
3
Note 1. When using MDS-B-SVJ2
Note 2. When using MDS-B-V1/V2/V14/V24
OFF
ON
t
e
OFF
ON
OFF
ON
Emergency stop (EMG)
Dynamic brake actual operation
Initial feedrate F
G0
Time
Feedrate
Coasting amount
Dynamic brake control