Watlow CPC400 - Manual (Page 59)

CPC400 Series User’s Guide Chapter 2: Installation
Doc. 0600-2900-2000 Watlow Anafaze 45
Signal Common
For usual installations, do not connect the dc commons of
the controllers together or to the converter or host device.
Termination
For EIA/TIA-485 signals to be transmitted properly, each
pair must be properly terminated. The value of the termi-
nation resistor should be equal to the impedance of the
communications cable used. Values are typically 150 to
200
Ω .
The receive lines at the converter or host device should be
terminated in the converter, the connector to the host de-
vice or the device itself. Typically the converter documenta-
tion provides instructions for termination.
Use a terminating resistor on the receive lines on the last
controller on the 485 line. Set jumper JU1 in position B to
connect a 200
Ω
resistor across the receive lines. See
Changing the Hardware Communications Protocol on page
157.