Watlow CLS200 - Manual (Page 48)

Chapter 2: Installation CLS200 Series User’s Guide
32 Watlow Anafaze Doc.# 0600-3050-2000
and each should be connected to ground at
the process end.
• Connect the earth ground terminal on TB2
to a good earth ground, but do not connect
the analog common to earth ground. The
CLS200 uses a floating analog common for
sensor measurements. The noise protection
circuits on the sensor inputs function cor-
rectly only when the controller is correctly in-
stalled. See Ground Loops on page 24.
RTD Input Connections
This input type requires scaling resistors. Watlow Anafaze
recommends that you use a 100
Ω
, 3-wire platinum RTD to
prevent reading errors due to cable resistance. If you use a
2-wire RTD, jumper the negative input to common. If you
must use a 4-wire RTD, leave the fourth wire unconnected.
Figure 2.17 RTD Connections to CLS204 or
CLS208
Reference Voltage Terminals
The +5V Ref and Ref Com terminals are provided in order
to power external bridge circuits for special sensors. Do not
connect any other types of devices to these terminals.
Voltage Input Connections
This input type requires scaling resistors. Special input re-
sistors installed at Watlow Anafaze divide analog input
voltages such that the controller sees a -10 to 60 mV signal
on the loop.
100 Ω RTD
IN +
IN -
Com
CH
CH