Watlow CLS200 - Manual (Page 50)

Chapter 2: Installation CLS200 Series User’s Guide
34 Watlow Anafaze Doc.# 0600-3050-2000
Pulse Input Connections
The CLS200 can accept a pulse input of up to 2000 Hz from
a device such as an encoder. The frequency of this input is
scaled with user-set parameters. See Setup Loop Input
Menu on page 82 and Chapter 9, Linear Scaling Examples.
This scaled value is the process variable for loop 5 on a
CLS204, loop 9 on a CLS208, or loop 17 on a CLS216.
The CLS200 can accommodate encoder signals up to 24V Î
(dc) using a voltage divider or can power encoders with the
5V
Î (dc) from the TB50 or TB18. The following figures il-
lustrate connecting encoders. A pull-up resistor in the
CLS200 allows open collector inputs to be used.
NOTE! If the signal on the pulse input exceeds
10kHz the controller’s operation may be dis-
rupted. Do not connect the pulse input to a
signal source that may exceed 10kHz.
Figure 2.20 Encoder with 5VО
О О О
(dc) TTL Signal
Figure 2.21 Encoder Input with Voltage Divider
For encoders with signals greater than 5V Î (dc), use a volt-
age divider to drop the voltage to 5 volts at the input. Use
appropriate values for R
1
and R
2
depending on the encoder
excitation voltage. Be sure not to exceed the specific cur-
rent load on the encoder.
Pulse Input
Com
Encoder
+5V Î (dc)
10 k Ω
CLS200 and TB50 or TB18
Pulse Input
Com
Encoder
+5V Î (dc)
10 k Ω
R2
R1
CLS200 and TB50 or TB18