nvent 910 Series Installation, Operating And Maintenance Instructions page 12

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The following tables define the appropriate signal connections for the various types of interfaces:
RS-485 (2-Wire) Connections
Communication Signal
Receive/transmit data (+)
Receive/transmit data (-)
Shield
RS-232 (3-Wire) Connections
Communication Signal
Receive data
Transmit data
Common
Modem Interface Connections
Communication Signal
Modem
Modem
Shield
2.7.5 POWER CONNECTIONS
All of the power terminals are labeled for easy identification. Do not attempt to use wire sizes
that exceed the marked terminal ratings and avoid terminating two wires on the same terminal
whenever possible.
Always be sure that all terminals are adequately tightened according to the terminal
manu- facturer's specification. See Appendix A for allowable wire sizes, recommended
insulation strip lengths, and tightening torque. A loose terminal can cause arcing and damage
to the terminal or incorrect operation of the controller.
IMPORTANT: Make sure that power terminals are retightened several days after installation.
Stranded wire will tend to compress when initially installed; therefore, these terminals should
be checked for tightness several times after the system is installed to ensure that a good
connection is maintained. Be certain to use the proper size screwdriver for the terminal blocks
to minimize the chance of damage to the terminals.
If the controllers are installed in either a metallic or non-metallic enclosure, follow the
enclosure manufacturer's recommendations for proper grounding. Do not rely on conduit
connections to provide a suitable ground.
Grounding terminals/screws are provided for connection of system ground leads. Proper
system grounding is required for safe and correct operation of the controller's protection
features.
2.7.6 INPUT POWER
The 910 controller may be powered directly from a 100 to 277 Vac circuit. The wiring terminal
assignments are defined below.
Power Connections
Line/L1 power input
Neutral/L2 power input
Line/L1 output to trace
Neutral/L2 output to trace
Wiring diagrams for typical configurations are included in Appendix C.
CAUTION:
Many wiring configurations will use more than one power source and all must be de-energized
prior to performing any maintenance on a controller circuit.
Terminal No.
16
17
18
Terminal No.
16
17
18
Terminal No.
16
17
18
Terminal No.
A
B
C
D