23
Voltage follower
Instead of using a speed adjust potentiometer, the drive may be
wired to follow an analog input voltage signal that is isolated from
earth ground (Figure 12). Connect the signal input (+) to S2.
Connect the signal common (–) to S1. Make no connection to S3.
A potentiometer can be used to scale the analog input voltage. An
interface device, such as Minarik model PCM4, may be used to
scale and isolate an analog input voltage.
With either 115 VAC or 230 VAC line voltage, an analog
input voltage range of approximately 0–1.4 VDC is required to
produce an armature voltage range of 0–90 VDC. With 230 VAC
line voltage, an analog input voltage range of approximately 0–2.8
VDC is required to produce an armature voltage range of 0–180
VDC.
Figure 13. Voltage Follower Connections
Installation