Cobra Electronics CPI 2550 - Manual (Page 7)

9 Nothing Comes Close to a Cobra ® 8 English
Connecting Cables (not included)
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Power wire and wiring are very important to the performance of
the inverter. Because the inverter has a low voltage, high
current input, low resistance wiring is essential between the
battery and inverter. This is so it can deliver the maximum
amount of energy to the load.
Use only copper wire. Aluminum wire has about one-third
more resistance than copper wire of the same size, plus it is
difficult to make good, low-resistance connections to
aluminum wire.
We recommend two #4 AWG copper cables (90°C insulation
rating) as the minimum size for connections between the
battery and inverter.
Keep the cable length as short as possible, no more than
four feet (one and one-half meters). This will keep the
voltage drop to a minimum.
If the cable has too much voltage drop, the inverter
may shut down when drawing higher currents because
voltage at the inverter may drop below 10 volts. If you must
use longer cables, choose thicker cables, such as #2 AWG,
and trim the ends of the cable to fit the terminals.
To connect the cables between the inverter
and the battery:
1. Turn the On/Off Switch on the inverter to the off position. If
the power source is a DC power supply, switch it off as
well.
2. On the end of the cable that connects to the inverter, strip
back the insulation about one-half inch (one and one-half
cm), exposing the bare copper conductor.
3. Connect cables to the Power Input Terminals on right side
panel of the inverter. The red terminals are positive (+) and
the black terminals are negative (-). Insert the bare ends of
the cables into the terminals and tighten the screws to
clamp the wires safely.
4. Connect cables to the power source:
a. Connect each cable from the Negative (Black) Terminals
of inverter to the Negative Terminal
of the power source. Make a secure connection.
b. Connect each cable from the Positive (Red) Terminals of
the inverter to the Positive Terminal
of the power source (the battery’s main fuse or
the battery selector switch, if you are using one). Make
a secure connection.
Connecting Cables Connecting Cables
Installation Installation
On/Off Switch to Off
Strip the Insulation
Insert Bare Cables
Connect Cables