Will a bigger inverter avoid the dreaded alarm?

profdant139 wrote:

So that is my question -- if I get a bigger inverter, will it still drop to 11 volts and emit that shriek? Would a bigger inverter charge the laptop?

You don't mention the size of the inverter or how it is wired. If it is going through a 12V socket, it doesn't matter what size it is - the 12V socket only allows up to @110 watts.

Using my 150W inverter and a 12V socket (110W), I can either charge my laptop or I can use my fully charged laptop; I cannot both charge the battery and use the laptop. The wattage draw is too large for the socket.

I have three inverters: one alarms at 12V, one alarms at 11.5V, and one shuts down at 11.4V. Unless it is programmable (like my last one), you are at the mercy of the manufacturer.

Larger wires will not stop the alarm at 11V if your battery is actually reaching 11V. Larger wires will help the laptop charging issue provided the inverter is large enough for the load.

A larger inverter will not fix any of the above problems if it is not hard wired (12V socket limit). If it is hardwired, you will still have the problem of tripping at whatever preset the manufacturer set.

Acampingwewillgo wrote:
Just wondering, can't you charge most cell's and laptops from USB ports off a 12 volt power source rather than inverting to 120 than converting back to 12-15 volts? Just asking...not sure myself!

tablets, cell phones yes... real laptops, no. they usually require 18 volts. yes, you can buy a 12v to 18v dc converter, but that is a single purpose beast, versus the inverter that provides more usefulness

Here is a link to the Samlex site (they sell solar inverters), which states that you need at least #4 wire for a 10' run!

&http://www.samlexamerica.com/documents/product-specs/12013-DC%20Install%20Kits-0815_Hrez.pdf

I have their install kit in my pickup and I don't get the alarm from the inverter for low input voltage, I have tripped the internal breakers on my 2000w inverter when I drew to much load.

BTW #2 wire is the size of a pencil, for each leg.

Just wondering, can't you charge most cell's and laptops from USB ports off a 12 volt power source rather than inverting to 120 than converting back to 12-15 volts? Just asking...not sure myself!

Bigger, shorter wires and/or second battery.

I agree with two of the posts above, that #10 wire between the inverter and the battery will work well, and there will be much less voltage drop to the inverter.

You seem to rarely need the inverter, so a larger one seems not required. Either way, you probably would need #8 wire for the larger inverter, and the small one will barely have any voltage drop across the really large wire.

Also make sure that the return wire is also copper wire to the battery, so that you are not using the steel frame to conduct power back to the battery.

Check the battery for loose connections. A loose connection such as the battery ground can cause momentary voltage loss that you described.. .

By the way, a larger inverter would also require dual batteries. Dual batteries, and your voltage drop would be much less, so not requiring the replacement inverter.

Also a solar panel can allow the battery to be fully charged and be in much better condition before a trip starts. SunElec.com has a 140 watt solar panel for about $229 that has a aluminum frame. It will work great on any RV!



GOod luck,

Have fun camping!

Fred.

As Westend said, it depends on the set-point for the alarm.
And different manufactures use different set-points.

If the wires to the inverter (input) are too small, there will be a voltage drop. Usually this is more of an issue with larger inverters that need hose size wires, but it still might be something worth looking at...especially if you are connected to the trailer wiring rather than using a dedicated wire to the battery.

When batteries get older (and colder), they have less capacity. Maybe it's time to replace your battery.

Winter camping takes lots of battery power. Any chance you can add a second battery?

I know we have discussed it before, but a heater that doesn't use a battery sucking fan makes a huge difference.

Are you still planning on going to the Canyons later on this month?

You might just need fatter wires between the inverter and battery.

If you plug the inverter into a 12v socket then that leads to long thin wires which is the problem. If it also comes with a set of wires for battery clamps then use those instead of the 12v plug set directly on the battery. Or if you need to do this inside the rig, you can clamp to the battery lugs on the DC panel which also has the converter's wires to it. The wires from the lugs to the battery will be fatter than from the 12v socket (on the Winegard panel, eg) and might make the difference.

Getting a bigger inverter won't help with this.

You need larger 12 volt wire to the inverter to reduce the voltage drop.

I'd guess if your bigger inverter has an alarm setpoint of say, 10.5 V it will be better but if it has the same 11V setpoint, it will function the same. The draw from the battery is what's bringing your voltages down, not the function of the inverter.

I'd assume from your statement about the laptop charger causing an alarm that you have a small MSW inverter. By all means, upgrade to a bigger PSW inverter. I recommend the Xantrex Prowatt 1000W inverter. It is silent, durable, and comparatively inexpensive.