Light trips breaker

Hi Bobbi
A 50w Headlamp will draw 4 Amps (Ohms Law 50/12=4.1)
So... 2 Low beams will draw 8 Amps.
Obviously more for high beam and high wattage Quartz Bulbs.
That is a lot for a small switch (contacts) to handle.
This is why a lot of vehicles use a Relay to power the Headlamps.
The relay is connected directly from the Battery to the Headlamps.
The large internal contacts can handle the higher current (30A) and the dash headlight switch connects to the magnetic coil inside the relay and is only used to pull the contacts closed.
Does your circuit include a relay.? Do you hear a relay click?
simple headlight relay wiring

To assist with your troubleshooting, try disconnecting one head lamp bulb to reduce current load. Does the fuse blow?
A temporary12v circuit breaker could be substituted for the fuse until you determine the problem.


If the circuit is using a relay then there will be a fat wire going from the battery to the Relay. The fine wire on the relay input is the trigger. A 12v test lamp is really useful for troubleshooting around the car. Also a cheap multimeter. Clamp style current meter is also handy to see exactly what current is blowing the fuse

Relays

http://www.ebay.com.au/itm/NARVA-CIRCUIT-BREAKER-REPLACES-STANDARD-BLADE-FUSE-BATTERY-15A-AMP-12V-55715-/321234642731?hash=item4acb13a72b
There is a 10A circuit breaker also like above

Automotive Circuit Breakers Wiring Products

Breakers trip because of heat.
When heat from wire exceeds breaker rating, it trips.
Something is causing heat on the wire, wire is too small for the amp draw, there is short circuit, or breaker is bad.
Replace breaker and/or test wire.

Put amp-meter on wire and read amp draw through wire.
Amps cause heat. That's why high voltage lines from power station are high-volt-low-amp so there is no heat loss with long distance transmission, until transformer at home converts electricity to lower volts and high working amps with enough power to run electrical devices.
Same is true for AC and DC circuits.
If amp reading on wire exceeds rating on breaker for length of time, then breaker will trip.
The fact that the breaker lets current (amps) to flow for a period of time before tripping is because the breaker is probably rated for slow-acting, or it takes a while for amp draw to heat the wire.

Following image shows amp-meter that clips over wire to get amp reading.
http://waterheatertimer.org/pdf/Which-is-best-gas-water-heater.pdf

If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

There seem to be several questions mingled in with those 2 questions.

1) Amps can go either way

2) Breakers trip when heat exceeds certain level. Heat is caused by amps.

3) You want to add a subpanel in garage.
I do not know the code in your area for installing a subpanel.
Your plan will work by connecting 6 gauge wire to main breaker, and new 60 amp breaker will protect wires between main box and subpanel.
Remember, wires going into main breaker cannot be turned off without pulling meter.
Some areas require license to pull meter.
http://waterheatertimer.org/How-to-replace-circuit-breaker.html

4) To work around license and meter-pull, simply replace a 240V breaker in main panel with your new 60 amp breaker.
Then move breakers around to match new set-up.
New subpanel can accommodate two new 240V breakers and one new 120 Breaker
http://waterheatertimer.org/How-to-install-a-subpanel.html

5) 6 gauge wire is correct for 60 amp breaker.

6) I'm not sure what you mean by the box rails?

7) Do you need more amperage on main service?
This means adding a larger service panel with 150 Watt or 200 Watt main breaker.
Some areas require service upgrade when remodeling or adding circuits.

8) How to figure total amp draw at your house.
Add up total watts being used.
For example you have 1/2 Hp motor
754 watts per Hp
1/2 Hp = 377Watts
Volts x Amps = Watts
Amps = Watts divided by Volts.
377 Watts divided by 240Volts = 1.57 amps (plus a bit more amperage when motor starts)
40 watt light bulb divided by 120Volts = .33 amps
Double oven has label located inside door that shows upper and lower wattage.
Dishwasher, dryer, big screen TV, satellite receiver all have labels that show wattage.
Water heater has label that shows wattage of each element.
http://waterheatertimer.org/Figure-Volts-Amps-Watts-for-water-heater.html
http://waterheatertimer.org/See-inside-main-breaker-box.html

Add a comment for more help

Replace the breaker in the house circuit it is probably weak, make sure you replace it with the correct size and don't be tempted to go bigger unless your confident that your wiring is good and can handle a bigger breaker. If the breaker continues to trip you may have a fan that is bad and drawing too many amps

No,you can not wire directly to a meter. All wiring must come through the circuit panel or sub panel.
150 amps is sufficient to run what you describe. You may have a weak main breaker or loose wiring to these appliances. Place a amp meter on a incoming supply wire at the main, while you monitor amp draw have someone go around the house and turn on all these appliances. If it trips at less than 140 amps you have a bad main.
I suspect you will find a bad neutral wire on one of these appliances.

Are the bulbs out of the sockets and the fuse blows?
Take bulbs out and check again
Place one back at a time if fuse was OK with bulbs out to locate bad bulb.
Otherwise.......
Do this........if still needed with bulbs out and fuse blowing.
Put a circuit breaker in to replace the fuse of the same amperage.
It will trip off then back on.
Use a standard cheap magnetic compass........place along lighting wiring........the wire with current will cause the needle to jump as circuit breaker trips on and off.
Follow path of current to problem.....the compass will stop moving once past the shorted /grounded wire/connection.

It won't take much to trip the GFI. Have you tried to dry the fixture out completely? Use a blow dryer and remove any moisture. Also, remove the light and cap the wires and try it if you can, it might be the wire.

If you need further help, I’m available over the phone at https://www.6ya.com/expert/craig_3fa289bf857b1a3c

sounds like a loose connection ,or possibly a weak main breaker.

Possible overcharge or bad breaker. You need to check the amp draw for the unit. If you draw under full load amps and trips breaker breaker is bad.Rus

Since power = voltage X current, 1.58kW / 120VAC = 13.166A

So this unit should be fine on a 15A breaker unless the breaker is bad, the wiring or a connection is loose somewhere between the breaker and the microwave, or the microwave's magnetron or high voltage transformer are failing and drawing extra current.

Microwaves should really be on the own separate breaker if at all possible. Plus, the more a breaker trips, the more work out it gets.

Have you measured the voltage at the outlet? If that's off, current and power will be affected. It should be about 110-125VAC.

A good power test for outlet and wiring integrity is a toaster, toaster oven, or hair dryer rated at about 1500 watts.

If it doesn't run and heat steadily, then there may be a problem with the house wiring or breaker.

If it passes this test, the problem is likely in the microwave.

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