Qualitrol 118 Series Instruction Manual page 9

E l e c t r o n i c T e m p e r a t u r e M o n i t o r
Figure 3. Wiring Diagram
RS-485 Link (optional)
The optional RS-485 data link is accessed through a terminal block connector on
the side of the unit. This provides a method of communicating with a remote
master station using Modbus RTU protocol. Refer to Appendix E of this manual
for additional information. See Figure 4; RS-485 Wiring Diagram.
NOTE: DO NOT install or remove jumper or connector when the unit is
powered.
Figure 4. RS-485 Wiring Diagram – 118P
Figure 4. RS-485 Wiring Diagram – 118H
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