USB Plug Addition

[mikef]

I want to tap into the 12v line going into my water pump and add on a USB 5v 2.1a plug for phone charging.

Alternatively I would use a 12v cigarette lighter jack which would allow me to also use a small 300w inverter or a USB plug.

Any items I should consider. The power draw should be very minimal.

[TLB]

Water pump power goes through a switch, but you already knew that.
Switch would be off at full hookup sites.

[mikef]

Originally Posted by TLB

Water pump power goes through a switch, but you already knew that.
Switch would be off at full hookup sites.

True, hadn't considered the switch. It is so easily accessed. I'll have to look on the underside for a better option. Thanks.

[TLB]

Post your model number, maybe others have an idea for power connection.

[mikef]

Originally Posted by TLB

Post your model number, maybe others have an idea for power connection.

2400bh is the model. Water pump is on the left side of the bed. It does have two LED lights over the top of the bed under the storage doors. Thx.

[TLB]

Originally Posted by mikef

2400bh is the model. Water pump is on the left side of the bed. It does have two LED lights over the top of the bed under the storage doors. Thx.

Ok you have power near by so shouldn't be too hard to find the wires going to those lights.

[SummitPond]

I'm not familiar with that model or floorplan - do you have a TV in the bedroom area? Our antenna booster control has a 12V socket built into it, but it's nowhere near the bed (but in our trailer, it's not really that far either!)

If you were to tap off the LED circuit you'd have to parallel off the bulb. Does the light have a separate switch on it so it could be turned off?

I replaced one of my 120V outlets next to the bed with one that has the 5V USB ports built-in. Due to the design of the outlet I needed a new junction box, but it was an easy enough mod.

[JRTJH]

Originally Posted by mikef

I want to tap into the 12v line going into my water pump and add on a USB 5v 2.1a plug for phone charging.

Alternatively I would use a 12v cigarette lighter jack which would allow me to also use a small 300w inverter or a USB plug.

Any items I should consider. The power draw should be very minimal.

If I'm reading your question correctly, there's a couple of issues that you may not have considered.

First: if you're going to plug in a 300 watt inverter, the DC power requirement to provide 120VAC/300 watts (2.5 amps) is 28 amps of DC power. FEW (if any cigarette lighter plugs are capable of providing that much amperage. Those that are "strong enough" are wired separately and not "split off from the water pump" which is usually on a 15 amp DC fuse.

Second: If you do wire a USB 5/2 amp charger socket into the water pump wiring, you may find (probably will find) that when the water pump turns on, you'll get a voltage drop on the USB ports. That's from the spike in power required to operate the water pump, the voltage drop in the wiring that supplies both and the voltage regulator circuits in "most" inexpensive USB charger adapters. While it probably won't damage the USB charger, you may find that over time, you'll damage the charging circuits in your sensitive rechargeable electronic devices.

I'd recommend that if you are going to power a 300 watt inverter, you use at least 12 ga wiring (preferably 8 ga wires if the run from the battery to the socket is greater than 6 or 8 feet). That power needs to be a separate (not split off from anything) circuit. If you're going to "wire a USB charger into any circuit, make it one that doesn't have a DC motor on the wiring: ie, avoid the furnace, water pump and any fan wiring as possible DC sources for the charger.

[mikef]

Originally Posted by SummitPond

I'm not familiar with that model or floorplan - do you have a TV in the bedroom area? Our antenna booster control has a 12V socket built into it, but it's nowhere near the bed (but in our trailer, it's not really that far either!)

If you were to tap off the LED circuit you'd have to parallel off the bulb. Does the light have a separate switch on it so it could be turned off?

I replaced one of my 120V outlets next to the bed with one that has the 5V USB ports built-in. Due to the design of the outlet I needed a new junction box, but it was an easy enough mod.

The TV isnt too far but on the opposite end. I have 120v under the bed but looking for 12v near the shelf next to bed. I'll have to look under the unit when able, lots of snow in Chicago burbs tonight.

Thanks.

[mikef]

Originally Posted by JRTJH

If I'm reading your question correctly, there's a couple of issues that you may not have considered.

First: if you're going to plug in a 300 watt inverter, the DC power requirement to provide 120VAC/300 watts (2.5 amps) is 28 amps of DC power. FEW (if any cigarette lighter plugs are capable of providing that much amperage. Those that are "strong enough" are wired separately and not "split off from the water pump" which is usually on a 15 amp DC fuse.

Second: If you do wire a USB 5/2 amp charger socket into the water pump wiring, you may find (probably will find) that when the water pump turns on, you'll get a voltage drop on the USB ports. That's from the spike in power required to operate the water pump, the voltage drop in the wiring that supplies both and the voltage regulator circuits in "most" inexpensive USB charger adapters. While it probably won't damage the USB charger, you may find that over time, you'll damage the charging circuits in your sensitive rechargeable electronic devices.

I'd recommend that if you are going to power a 300 watt inverter, you use at least 12 ga wiring (preferably 8 ga wires if the run from the battery to the socket is greater than 6 or 8 feet). That power needs to be a separate (not split off from anything) circuit. If you're going to "wire a USB charger into any circuit, make it one that doesn't have a DC motor on the wiring: ie, avoid the furnace, water pump and any fan wiring as possible DC sources for the charger.

I will plan to look under the unit and see about a direct wire hookup. Thanks.

[Logan X]

I recently added USB ports to each side of the bed. I tapped into the 12v light on the bottom of the cabinet which is over the bed. I ran romex through the hollow space on the bottom of the cabinet and down the side of the closet. It seems to be working out good.

[mikef]

Originally Posted by Logan X

I recently added USB ports to each side of the bed. I tapped into the 12v light on the bottom of the cabinet which is over the bed. I ran romex through the hollow space on the bottom of the cabinet and down the side of the closet. It seems to be working out good.

Looks like a good approach. I believe I can do the same. Appreciate the info. Thanks.

[chuckster57]

Rule of thumb when using an inverter: place it as close to the DC source as possible. Less voltage drop from battery(s) that way, and be sure to use the recommended gauge wire.

[mikef]

Originally Posted by chuckster57

Rule of thumb when using an inverter: place it as close to the DC source as possible. Less voltage drop from battery(s) that way, and be sure to use the recommended gauge wire.

Thanks for the advice. Makes sense.

[notanlines]

Another plus for your USB add-ons to have their own circuits and heavy gauge wire is less chance for TV buzz (interference) when in operation, especially with OTA reception.

[oldtimer]

I suppose that you have already thought about changing or adapting a close-by regular 120V outlet to have an integral USB outlet. This could be a replacement duplex outlet with USB, or a plug in 120 volt "plate" with a USB outlet.

[mikef]

Originally Posted by oldtimer

I suppose that you have already thought about changing or adapting a close-by regular 120V outlet to have an integral USB outlet. This could be a replacement duplex outlet with USB, or a plug in 120 volt "plate" with a USB outlet.

Thanks for the post. I thought about it but the plugs a a little too far away. The design is a bit awkward. Items are usable, but not useful based on placement.

[Logan X]

Mikef-the USB outlets I installed have a led light to indicate it’s receiving power. That light creates a small parasitic draw on the battery. I installed a power switch in line before the USB port so i can turn off the power to the port when I’m not using it and I eliminate the unnecessary battery draw. I just wanted to mention this Incase you have a similar situation.

[bowchik]

We have a power outlet between the two reading lights above the bed, my husband installed one there. It has a 12v plug for his c-pap machine and 2 usb ports.

[bbells]

IMHO, it is much easier to just connect to the power line of the stereo. It is 12v in most vehicles, and in a much easier location to connect to.