PowerTec 1000 User Manual

Model
1000
Installation and Operation Manual
Page
21
OFFICIAL 6/1/2001
H
OW
D
O
I …
CONNECT AN ANALOG SPEED REFERENCE?
The analog speed reference for the Model 1000
and 1000A is 0 to +10 VDC with the positive
connection on TB2 terminal 10 and the common
connection on TB2 terminal 12. Voltages less than 0
VDC have no effect and voltages greater than 10 VDC
become non-linear.
The input impedance is in excess of 100K when
the drive is in RUN mode, and about 30 K when the
drive is not in RUN mode. Using a speed
potentiometer with a resistance greater than 10 Kohms
may result in non-linear operation of the speed pot.
There is a +10VDC source at TB2 terminal 9. The
supply has a 10 ma limit.
There is a 1000 ohm potentiometer, connected as
a rheostat, for MINIMUM SPEED between TB2-11 and
common. With a 10K external speed pot, this allows a
minimum speed adjustment of up to about 9% of full
speed. You may connect the low end of the speed pot
directly to TB2 terminal 12, bypassing the MIN SPD
pot.
Enclose the wires to a speed pot in a shielded
cable, for noise reduction. Connect the shield only at
the drive end, on TB2 terminal 12.
The reference voltage for the input does not have
to come from the reference source at TB2 terminal 9.
You can introduce an external reference voltage
between TB2 terminals 10 (+) and 12 (common). The
speed of the motor varies as the external voltage
varies.
If you use an external “current source” speed
control (such as a 4 to 20 ma signal), you must convert
it to a voltage. Then you may introduce this voltage as
a speed command to TB2 terminal 10 (+) and TB2
terminal 12 (-).
When using a speed pot or an external voltage, it
is not necessary to reduce the speed signal to zero
before starting the drive. Starting the drive with a speed input already present will not damage the drive,
even at very high accel rates.
The Brushless DC drive operates over very wide speed ranges, so when you want the motor to stop
with the drive in RUN mode, there must be ZERO VDC at the input. Voltages as low as 70 millivolts (0.070
VDC) will cause the motor to turn. Noise levels on the reference line can reach these values. You must be
very careful about shielding and common mode voltages if you expect to operate with references of less
than 0.5 VDC.
TB2
16151413121110987654321 1817
+10VDC
REF IN
0 TO 10VDC
REFERENCE
10 OHMS
+
-
MIN
SPEED
TB2
16151413121110987654321 1817
+10VDC
REF IN
SPEED
POT
10K
CW
CW
10 OHMS

PowerTec 1000 Specifications

General

Brand	PowerTec
Model	1000
Category	Controller
Language	English