Table of Contents
Advertisement
SECTION 9 - Brushless Motor Control
The curves at right depict trip characteristics
for three cases of programmed set-points as
follows:
A
Stall Time -
30 Sec
Locked Rotor -
6XFLC
B
Stall Time -
10 Sec
Locked Rotor -
6XFLC
C
Stall Time -
2 Sec
Locked Rotor -
6XFLC
This protection is enabled when motor is
started and disabled when power factor pro-
tection is enabled (concurrent with FCX
Relay pickup).
T
I
M
E
I
N
S
E
C
0
N
D
S
2000
1500
!,
1000
900
800
700
'"'\
\.
\
600
500
400
\
I'
I\.
,
\
300
200
150
100
I\.
\
\
~@
\
\
1\
®\I\.
90
80
\.
\.
\.
70
60
50
40
30
20
\
1\
\
\
\
\
'\
\
1\
1\
\
1\
,
\
15
10
\©
1\
9
8
7
"
6
5
~
4
3
1\
i\
2
.8.91
1.5 2
3
4
5 6 7810
Trip Current in Multiples of Programmed Full
Load Current
Figure 24. Brushless stall/acceleration protection characteristic
/-lSPM starts tracking motor cool down at approximately a 15-
minute time constant rate so that protection is provided against
abusing the motor from too frequent starting. Wait at least 15
minutes before attempting a restart on a motor that has been
shutdown from a stall protective operation, or one in which two
or
more rapidly successive start/stop operations have been
performed.
9.3.2 Power factor (pull-out) protection
The power factor protection for brushless control operates
as power factor protection for collector ring motors described in
Section 4.1.3. However, current 13 is derived internally to the
CR192/-lSPM by algebraically summing currents 11 and 12
inputs.
37
Advertisement
Table of Contents
