Advanced Marine Electrics and Electronics Troubleshooting A Manual for Boatowners and Marine Technicians

depending upon where you place the leads.

The readout identifies the voltage drop in the

positive and negative sides of the circuit as

separate values, which should save you a lot of

time in narrowing down the exact location of

the fault. (It’s usually at one end of the circuit

or the other, or any terminal point in

between.)

34 electrical systems troubleshooting

DC –

battery DC +

switch open

cabin light

• bus bar

fuse

inTELLECT EXP-1000

supplementary test

leads (provided with

meter)

+ bus bar

To calculate voltage drop, both of the inTELLECT EXP-1000’s lead sets are required. The battery test lead and the DMM

(digital multimeter) lead have different plug ends, so you can’t connect them incorrectly at the meter. Each lead has one black

and one red end clamp for attachment to the circuit.

Attach the red lead from the DMM lead on the positive side at the circuit’s source of power, and the black lead to

the negative side. At the other end of the circuit, connect the red battery lead to the positive connection, and the black

lead to the negative connection.

After entering the amperage draw value for the circuit, hit the “Next” key. The device will test the circuit and display

total circuit voltage drop. It will also display individual values for both the positive and negative return sides of the circuit,

saving several steps compared to the use of a traditional multimeter.

DC –

+ bus bar

battery

switch closed

cabin light

• bus bar

fuse

DMM or DVOM

fuse

DMM or DVOM

Using a conventional meter, you have to connect, disconnect, and reconnect both ends of the circuit to acquire the same

data. Then you would still have to perform some calculations to get voltage drop.

1

2