Data Flow Systems TCU800, Quick Start Manual, Page: 14 / 25

13
Wiring AC Power
The maximum wire size to TCU connectors is 12 AWG.
Use stranded copper conductors only with a minimum rating of 75°C.
The recommended circuit breaker is 10 Amp maximum.
When using connectors with screw-type terminals, tighten screw terminals to a maximum
7 in-lb (.79 Nm).
All AC source power wired to the TCU should be from the same leg of the three-phase
system. (Diagrams in this section show Phase C (L3) being used.)
The LCD screen and Status LED do not indicate that AC power has been removed. Even if
these indicators are not lit, you should assume that the TCU is still powered. To remove
power, you must turn off the external circuit breaker.
The TCU operates from 120 VAC. Verify the input voltage on the TCU’s connector label before wiring.
Three terminals are provided for wiring power:
•
P1-5, AC_PWR (AC power)
•
P1-6, AC_NEUT (AC neutral)
• P1-7, TGND (earth ground)
Terminal P1-7 is designated Earth or Safety ground. The TCU’s enclosure is also connected to the TGND
terminal. Wire in accordance with Federal, State, and Local Electrical Codes.
The transformer must provide AC neutral. When wiring to a typical three-phase, 4-wire, 240 Volt
transformer that provides AC neutral, refer to “Typical 240 Volt, 4-Wire Transformer” (next page). Refer
to “Typical 480 Volt, 3-Wire Transformer" (next page) when connecting to a typical three-phase, 3-wire
480 Volt transformer with no neutral provided. Note that these diagrams are for typical installations. If
your installation deviates from that shown here, refer to the National Electrical Code® (NEC®)
Handbook.