TX Matrix Plus DC Power Electrical Safety Guidelines
When working with DC-powered equipment, observe the following
guidelines:
The following electrical safety guidelines apply to a DC-powered
router:
- A DC-powered router is equipped with a DC terminal block
that is rated for the power requirements of a maximally configured
router. To supply sufficient power, terminate the DC input wiring
on a facility DC source capable of supplying at least 48 A –48
VDC. We recommend that the 48 VDC facility DC source be equipped with
a circuit breaker rated at 125% of the power provisioned for the input
minimum, or as required by local code. Incorporate an easily accessible
disconnect device into the facility wiring. In the United States and
Canada, the –48 VDC facility should be equipped with a circuit
breaker rated a minimum of 125% of the power provisioned for the input
in accordance with the National Electrical Code in the US and the
Canadian Electrical Code in Canada. Be sure to connect the ground
wire or conduit to a solid office (earth) ground. A closed loop ring
is recommended for terminating the ground conductor at the ground
stud.
- Run two wires from the circuit breaker box to a source
of 48 VDC. Use appropriate gauge wire to handle up to 60 A @ –48
VDC, or as required by local code.
- A DC-powered TX Matrix Plus router that is equipped with
a DC terminal block is intended only for installation in a restricted
access location. In the United States, a restricted access area is
one in accordance with Articles 110-16, 110-17, and 110-18 of the
National Electrical Code ANSI/NFPA 70.
 | Note:
Primary overcurrent protection is provided by the building
circuit breaker. This breaker should protect against excess currents,
short circuits, and earth faults in accordance with NEC ANSI/NFPA70. |
- Ensure that the polarity of the DC input wiring is correct.
Under certain conditions, connections with reversed polarity might
trip the primary circuit breaker or damage the equipment.
- For personal safety, connect the green and yellow wire
to safety (earth) ground at both the TX Matrix Plus router and the
supply side of the DC wiring.
- The marked input voltage of –48 VDC for a DC-powered
TX Matrix Plus router is the nominal voltage associated with the battery
circuit, and any higher voltages are only to be associated with float
voltages for the charging function.
- Because the TX Matrix Plus router is a positive ground
system, you must connect the positive lead to the terminal labeled RTN, the negative lead to the terminal labeled –48V, and the earth ground to the chassis grounding points.
Published: 2011-12-19