Motor Connector
( Brushed or 3 phase Brushless )
1
Phase C
2
Phase B (N/C for Brushed Motors)
3
No Connect
4
Phase A
Motor Connector
( 2 Phase Brushless [2PB] )
1
Phase B-
2
Phase B+
3
Phase A-
4
Phase A+
Operation
Commutation Related Velocity
When using sinusoidal commutation and higher speed applications, it is a good idea to calculate the speed at which
commutation can start to affect performance of the motor. In general, it is recommended that there be at least 8
servo samples for each magnetic cycle. The time for each sample is defined by TM, “TM 1000” is default and is in
units of μs per sample or [μs/sample]. TM can be lowered to achieve higher speeds.
Below is the equation that can be used to calculate the desired maximum commutation speed in counts per second
[cts/s]:
Speed
[
cts
/
s
]
=
m
×
10
6
(
TM
×
n
)
Where,
m
is the number of counts per magnetic cycle [cts/magnetic cycle]
n
is the desired number of (TM) samples per magnetic cycle (8 or more recommended) [samples/magnetic
cycle ]
Example:
Assume that an encoder provides 4000 [cts/rev] and that a motor has 2 pole pairs. Each pole pair represents a
single magnetic cycle.
m
can be calculated as follows:
m
=
4000
[
cts
/
rev
]
2
[
magnetic cycles
]
=
2000
[
cts
/
magnetic cycle
]
If “TM 250” is set and 8 servo samples per magnetic cycle is desired, the maximum speed in counts per second
would be:
Speed
=
2000
[
cts
/
magneticcycle
]
×
10
[
μs
/
s
]
6
250
[
μs
/
sample
]
×
8
[
samples
/
magnetic ccycle
]
=
1,000,000
[
cts
/
s
]
Setting up the Brushless Mode and finding proper commutation
Using the D3540 requires version 1.1d revision firmware or higher; be sure this is installed on your controller:
A4 – AMP-435x0 (-D3540,-D3520) ▫ 230
DMC-40x0 User Manual