RV 12V DC to AC buck boost xfrmr ok .?.

[ABeaconSolar]

: We have a customer with an RV.
: It was running on DC batteries originally, but they want to run it all on AC now.
: It has some 12V DC fuses and an inverter feeding some ac breaker-fed devices.
: Their inverter is not working and they want to get away from using DC batteries.

: Question: Can We use an AC buck-boost xfrmr to supply what was the 12V DC side .?.

PS/1: We know better than to try to supply alternating current devices with direct current, but we aren't so sure if there is a problem going the other direction. Have we forgot something ??

PS/2: Why would 12V DC devices have a problem receiving equivalent 12V AC power ??

PS/3: How else could we provide power without (not an option) rewiring the whole camper !?

 

[ptonsparky]

Feeding the lighting should work okay, but not anything else.

 

[kwired]

A true "universal motor" should run on AC or DC. But all others will be AC or DC only.

 

[ggunn]

: We have a customer with an RV.
: It was running on DC batteries originally, but they want to run it all on AC now.
: It has some 12V DC fuses and an inverter feeding some ac breaker-fed devices.
: Their inverter is not working and they want to get away from using DC batteries.

: Question: Can We use an AC buck-boost xfrmr to supply what was the 12V DC side .?.

PS/1: We know better than to try to supply alternating current devices with direct current, but we aren't so sure if there is a problem going the other direction. Have we forgot something ??

PS/2: Why would 12V DC devices have a problem receiving equivalent 12V AC power ??

PS/3: How else could we provide power without (not an option) rewiring the whole camper !?

I'm a little confused as to what you are getting at but it could be interpreted as you wanting to connect a transformer to DC. You know that that won't work, don't you?

 

[augie47]

I'm a bit confused also, but if they are wanting to eliminate the 12vdc stuff altogether, why don't you look at picking up the output of the DC > AC inverter with you AC and doing away with all the DC circuitry.

 

[ggunn]

I'm a bit confused also, but if they are wanting to eliminate the 12vdc stuff altogether, why don't you look at picking up the output of the DC > AC inverter with you AC and doing away with all the DC circuitry.

He said that the inverter is not working; between that and the thread title it looked to me as if he was wanting to connect 12VDC to a buck boost transformer. That sounds to me like a fairly efficient way to blow up a transformer.

 

[GoldDigger]

: We have a customer with an RV.
: It was running on DC batteries originally, but they want to run it all on AC now.
: It has some 12V DC fuses and an inverter feeding some ac breaker-fed devices.
: Their inverter is not working and they want to get away from using DC batteries.

: Question: Can We use an AC buck-boost xfrmr to supply what was the 12V DC side .?.

PS/1: We know better than to try to supply alternating current devices with direct current, but we aren't so sure if there is a problem going the other direction. Have we forgot something ??

PS/2: Why would 12V DC devices have a problem receiving equivalent 12V AC power ??

PS/3: How else could we provide power without (not an option) rewiring the whole camper !?

Assumptions:

1. The wiring that is currently set up for 12VDC may not be rated or installed in a way that would allow you to put 120VAC on the same wiring, even if you changed all of the connected devices to use 120V.
2. You want to eliminate all 12VDC from the system and run off 12VAC supplied from 120VAC shore power using a transformer.

That will potentially work. But some things like fluorescent or LED lights which were designed for 12VDC will not work on 12VAC.
Motors, maybe, and incandescent light bulbs, sure. But nothing that has actual electronics in it.
Wiring should be good for either AC or DC at the same voltage and current.
Switches designed for DC should be able to handle AC at the same voltage just fine. The other way around is not a sure thing.

 

[augie47]

He said that the inverter is not working; between that and the thread title it looked to me as if he was wanting to connect 12VDC to a buck boost transformer. That sounds to me like a fairly efficient way to blow up a transformer.

new meaning to the words "smoke test"

 

[ronaldrc]

Most across counter bulk boost transformers are general purpose transformers.

A general purpose transformer is what you need 120 volts input and 12 volts output.
If you are not sure if the AC will not damage some of your equipment make a DC power supply out of it by adding a Bridge rectifier and a filter cap. This would replace your Inverter, but would not work for emergencys.

Ronald

 

[hbiss]

It was running on DC batteries originally, but they want to run it all on AC now.
: It has some 12V DC fuses and an inverter feeding some ac breaker-fed devices.
: Their inverter is not working and they want to get away from using DC batteries.

Sounds like the inverter makes 120VAC out of 12VDC. So if you want to go with 120VAC you can feed that equipment by refeeding the breaker panel. For the 12v equipment, as was said, if it's resistive loads like incandescent lighting you can feed it with a step down 120 to 12 volt transformer. Anything else build a DC power supply by hanging a bridge rectifier and a big capacitor off the 12 volt side of that transformer.

-Hal

 

[K8MHZ]

Some RV terminology:

Inverter - Takes 12 VDC and makes 120 VAC

Converter - Takes 120 VAC and makes 12 VDC

The converter is basically a battery charger. In fact, it does charge the batteries when the engine or generator is not running.

It sounds like there is a problem with the converter or it's associated wiring. Why not make the proper repair instead of re-engineering and or re-wiring the RV?

 

[GoldDigger]

Some RV terminology:

Inverter - Takes 12 VDC and makes 120 VAC

Converter - Takes 120 VAC and makes 12 VDC

The converter is basically a battery charger. In fact, it does charge the batteries when the engine or generator is not running.

It sounds like there is a problem with the converter or it's associated wiring. Why not make the proper repair instead of re-engineering and or re-wiring the RV?

I have seen at least as many occasions where "converter" refers to an inverter/charger/transfer switch combination. It has two inputs: shore power and house battery (the latter actually an input/output) and the AC out to loads. In some cases it is actually fed from a shore power/generator manual transfer switch.
The separate units, if they exist, would be an inverter and a charger.
A converter converts both ways.

 

[K8MHZ]

I have seen at least as many occasions where "converter" refers to an inverter/charger/transfer switch combination. It has two inputs: shore power and house battery (the latter actually an input/output) and the AC out to loads. In some cases it is actually fed from a shore power/generator manual transfer switch.
The separate units, if they exist, would be an inverter and a charger.
A converter converts both ways.

Those are called 'inverter/chargers'.

http://www.adventurerv.net/freedom-modified-1000w55-amp-sine-wave-invertercharger-p-2554.html

This is a converter

http://www.adventurerv.net/8900-series-electronic-converter-center-amps-p-7229.html

I see that the inverter chargers can get pretty pricey. If the OP has an inverter/charger that needs replacement, I guess I could understand the seeking of an alternative.

Maybe purchasing the converter and inverter separately and using a manual transfer switch?