User guide

ManualsBrandsBlue Sea Systems ManualsControl panel8023 Traditional Metal DC Panel - 8 Positions

Wiring Diagram

DC Power Distribution Panel

(PN 8023 /PN 3023 shown for reference)

Installation (continued)

TO DC

NEGATIVE

FROM DC

POSITIVE

FUSE

1.0 TO 2.0A

DC BACKLIGHT

BOARD

Wire Sizing Chart

1. Calculate the maximum sustained amperage of the circuit. Measure

the length of the circuit from the power source to the load and back.

2. Does the circuit run in an engine space or non engine space.

3. Calculate Famps (Feet x amps). Multiply circuit length by max. current.

4. Base the wire on either the 3% or 10% voltage drop. In general, items

which affect the safe operation of the boat and its passengers (running

lights, bilge blowers, electronics) use 3%; all other loads use 10%.

5. Starting in the column which has the right voltage and voltage drop,

run down the list until arriving at a value which is greater than the

calculated Famps. Move left to the Ampacity column to verify that the

total amperage of the circuit does not exceed the maximum allowable

amperage of the wire size for that row. If it does, move down until the

wire ampacity exceeds the circuit amperage. Finally, move left to the

wire size column to select the wire size.

Example

a. A 12 volt system at 10% drop with a 40’ circuit x 45 amps = 1800

Famps. A wire size of 8 is required.

In Boatowner’s Illustrated Handbook of Wiring, Charlie Wing identiﬁ es

three purposes of DC Grounding:

1. Holding conductive housings of low voltage (under 50 volts) DC

devices at ground potential by providing a low resistance return

path for currents accidentally coming into contact with the device

cases.

2. Providing a low resistance return path for electrical current,

preventing stray currents that may cause corrosion.

3. Grounding metal electrical cases to prevent emission from inside

or absorption from outside of radio frequency noise (RFI).

ABYC requires that grounding wires be sized no smaller than one wire

size under that required for current carrying conductors supplying the

device to which the grounding wire is connected.

A full treatment of this subject is not possible within the scope of these

instructions and there is controversy surrounding the general subject of

DC bonding, of which DC grounding is a component. It is suggested

that installers not familiar with this subject consult one of the reference

books listed elsewhere in these instructions.

8. Apply branch circuit labels and mount panel

Apply a label for each of the branch circuits from the 30 basic labels

provided. If the appropriate label is not included, the Extended Label

Set of 120 labels may be ordered from your marine supplier (PN 8039).

Individual labels are also available from Blue Sea Systems for speciﬁ c

applications. Refer to the label order form for a complete listing of

individual labels.

Fasten the panel to the mounting surface using the panel mounting

screws supplied with the panel.

9. Testing

Reconnect the main positive cable to the battery terminals and turn the

main switch on to supply power to the panel. Turn on all branch circuits

and test the voltage at the panel. Compare this voltage to the battery

terminal voltage to determine that the voltage drop is within 3%. With

all branch circuits still on, test the voltage at one device on each circuit

to determine that there is a 3% or 10% drop as is appropriate.

Optional Branch LED’s

This Panel is supplied with LED’s pre-installed in all optional branch

positions. For future expansion of the panels remove the positive leg of

the LED from the negative busbar and connect it to the load side of the

corresponding branch circuit breaker.

Note

This Blue Sea Systems electrical distribution panel is furnished with

15 amp AC/DC circuit breakers. This rating was selected to minimize

the need for removing the panel’s circuit breakers and reinstalling

different size circuit breakers. As shown in the Wire Sizing Chart

included with these instructions, even 16 AWG wire, which is the

minimum wire size recommended by ABYC, has an allowable

amperage greater then 20 amps. Additionally, it would be rare to have

more than 15 amps of current ﬂ owing in any one circuit. Therefore,

15 amp circuit breakers will satisfy the vast majority of marine circuit

protection situations.

The Purpose of a Panel

There are ﬁ ve purposes of a marine electrical panel:

• Power distribution

• Circuit (wire) protection

• Circuit ON/OFF switching

• Metering of voltage and amperage (In panels with meters)

• Condition Indication (circuit energized)