Running 115V repeater directly off of 12v?

[woodruff13]

I'm getting a Surecall Fusion4Home for my FR Forester 2401W.

This post is to ask folks about how to ditch the brick. The unit comes w/ a 115V to 5-15V converter, aka brick, aka wall wart.

But 115V in a 2401W only exists on shore power, or when the generator is running. We end up dry camping often.

Can I bypass the inverter / converter process? Rather than have an external inverter create 115V, and the supplied converter then create 5-15V, can I plug the Fusion4Home directly into the house DC supply, like I would a 12V TV? or my Music system?

Does someone make an isolator or filter to protect the input to the appliance when connecting to house battery?

I searched for a thread on this topic, but did not find the right keywords, I'm sure others have the same question.

Thanks, Bill

[formerFR]

most of us probably have no idea of what you are talking about...

[W5CI]

X 2

[rainman]

Bill

You will need to be sure that the wall wart is converting to DC current not AC. If DC then you should be good to go you will just need to include a fuse in the circuit to protect the system.

Rainman

[WoodLark-SC]

As long as your repeater can actually handle a 15v input (remember, when charging house battery you are looking at about 14v) you should be alright. Use a fuse, and make sure you get the polarity right.

[emm-dee]

I looked at the SureCall unit you’re talking about. It operates on any voltage between five and fifteen volts DC. You don’t need the brick...just a source for 12v which shouldn’t be a problem.

Look around the house and I bet you’ll find an old unused power supply that has a plug on the end of the cord that will fit the SureCall box. Cut it off and find a place to splice it into 12v in the motor home. I’m not familiar with the 2401 but looking at pictures makes me believe you can get power at the back of the Furion TV (Forester likes 12v TV sets) or on the other side pull the DVD/radio head and get 12v there.

My 3051 has factory installed 12 volt outlets at three locations. I use them to supply 12v directly to a Netgear router (for the rear camera), an amplified subwoofer and two 300 watt inverters used to power the AppleTV systems. Search around and you’ll probably find some on your unit.

[aircommuter]

You don’t need a filter, a battery is the purest form of DC power.

[Larry-NC]

Originally Posted by aircommuter

You don’t need a filter, a battery is the purest form of DC power.

X2

[5picker]

Originally Posted by woodruff13

I'm getting a Surecall Fusion4Home for my FR Forester 2401W.

This post is to ask folks about how to ditch the brick. The unit comes w/ a 115V to 5-15V converter, aka brick, aka wall wart.

But 115V in a 2401W only exists on shore power, or when the generator is running. We end up dry camping often.

Can I bypass the inverter / converter process? Rather than have an external inverter create 115V, and the supplied converter then create 5-15V, can I plug the Fusion4Home directly into the house DC supply, like I would a 12V TV? or my Music system?

Does someone make an isolator or filter to protect the input to the appliance when connecting to house battery?

I searched for a thread on this topic, but did not find the right keywords, I'm sure others have the same question.

Thanks, Bill

Yes. It will take 5-15v DC.
You may need something to connect to the R/V's DC system like alligator clips or a cigarette lighter plug and then to the proper sized plug on the repeater.

[Larry-NC]

Originally Posted by 5picker

Yes. It will take 5-15v DC.
You may need something to connect to the R/V's DC system like alligator clips or a cigarette lighter plug and then to the proper sized plug on the repeater.

You could do it much more elegantly than that in an hour.

• Find available 12v at a light switch, water pump or wherever.
• Mount a 12v outlet (AKA cigarette lighter socket) in the wall, nearby. If the circuit you're tapping is fused with more than 15 amps, tuck an inline fuse (5-10 amps) in the wall with the outlet.
• Find a cord with a plug matching the repeater's polarity. Put a cigarette lighter plug on the other end, paying attention to polarity.

Same result as 5picker's suggestion, but more elegant.

Larry

[jimmoore13]

Voltage is voltage - DC.
If your "device" requires 12 volts, you have what amounts to an infinite supply.
The device probably draws between miliamps and 3 or 4 amps at 12 volts.
Again, no problem.

Just be sure that the DEVICE wants 12 volts...not, for example, 5 volts. If you drive a 9 volt device with 12 volts continuously that could be an issue. And I see these repeaters cost about $400, so I'd be sure.

But there may be lots of magic going on in that wall wart....as you suggest, filtering and line conditioning. That might include driving the device with the required 9 volts (for example) instead of 12...or really more line 14 when hooked up to shore power and being hit with the charger. The only way to know is check with the device manufacturer.

I'd also be sure to kluge an in-line fuse to strictly limit amperage, because even 24 gauge wire from the wall wart cord to the plug will carry 20 amps or more for a little while before it becomes a fuse. That wall wart takes care to that, too.

Good luck. This seems like a fundamentally sound plan so long as you do your homework on the DEVICE's power requirements...what the wall wart says doesn't really matter. It's what the device wants that matters.

One more thing. You'll probably cut the cord off the wall wart to direct feed the device. Be sure to leave about 6" of wire attached to the wall wart just in case you need to put them back together.

[Larry-NC]

Originally Posted by jimmoore13

Voltage is voltage - DC.
If your "device" requires 12 volts, you have what amounts to an infinite supply.
The device probably draws between miliamps and 3 or 4 amps at 12 volts.
Again, no problem.

Just be sure that the DEVICE wants 12 volts...not, for example, 5 volts. If you drive a 9 volt device with 12 volts continuously that could be an issue. And I see these repeaters cost about $400, so I'd be sure.

But there may be lots of magic going on in that wall wart....as you suggest, filtering and line conditioning. That might include driving the device with the required 9 volts (for example) instead of 12...or really more line 14 when hooked up to shore power and being hit with the charger. The only way to know is check with the device manufacturer.

The OP stated that the device (not wall wart) specifications are 5-15 volts. This implies that the regulation is taking place within the device, not the wall wart.

Originally Posted by jimmoore13

One more thing. You'll probably cut the cord off the wall wart to direct feed the device. Be sure to leave about 6" of wire attached to the wall wart just in case you need to put them back together.

Why wreck the wall wart? When the OP is at his home (not his TT), he will need it.

The connector is almost certainly a coaxial barrel connector. That (and USB) are all anyone uses these days. It's likely not USB because USB is strictly 5 volts.

There are about six sizes of the coaxial barrel connectors. You used to be able to go into Radio Shack and they would match them for you. Now you need to find the drawings or here, get out your calipers, and then order from eBay or Ali Express.

As noted in a prior post, it's elegant to attach a 12v "cigarette lighter plug" to the barrel connector, making the adapter suitable for use in the travel trailer, the tow vehicle, or even the OP's pleasure vehicle.

Larry

[emm-dee]

View of the referenced device showing power input. Since it starts at five volts I’m sure there is internal regulation which reduces the input power to five volts, but it cannot handle anything over 15 volts.

[emm-dee]

Also, Frye’s stores have all the different barrel plug sizes.

[Larry-NC]

Originally Posted by emm-dee

View of the referenced device showing power input. Since it starts at five volts I’m sure there is internal regulation which reduces the input power to five volts, but it cannot handle anything over 15 volts.

Yes, that is a coaxial barrel connector. You need to make up a cord with a barrel connector (like on your wall wart) on one end and a cigarette lighter plug on the other end. The one I've linked will cost you the princely sum of 16 cents with free shipping. AND it includes a built-in fuse and on-off switch.

Here's an assembly already made up but I don't know if the barrel connector is the right size or whether the polarity is correct.

Unfortunately, the image of your device did not show the symbols that indicate whether the center is positive or negative, so you will have to measure your current supply and match it.

Or maybe just contact the manufacturer and ask whether they have a pre-made automotive supply cord for it.

Larry

Larry

[5picker]

Originally Posted by Larry-NC

You could do it much more elegantly than that in an hour.

• Find available 12v at a light switch, water pump or wherever.
• Mount a 12v outlet (AKA cigarette lighter socket) in the wall, nearby. If the circuit you're tapping is fused with more than 15 amps, tuck an inline fuse (5-10 amps) in the wall with the outlet.
• Find a cord with a plug matching the repeater's polarity. Put a cigarette lighter plug on the other end, paying attention to polarity.

Same result as 5picker's suggestion, but more elegant.

Larry

Sorry I wasn't more 'elegant'!
Geesh...

[aeblank]

Originally Posted by Larry-NC

Yes, that is a coaxial barrel connector. You need to make up a cord with a barrel connector (like on your wall wart) on one end and a cigarette lighter plug on the other end. The one I've linked will cost you the princely sum of 16 cents with free shipping. AND it includes a built-in fuse and on-off switch.



Here's an assembly already made up but I don't know if the barrel connector is the right size or whether the polarity is correct.



Unfortunately, the image of your device did not show the symbols that indicate whether the center is positive or negative, so you will have to measure your current supply and match it.



Or maybe just contact the manufacturer and ask whether they have a pre-made automotive supply cord for it.



Larry



Larry

I'd bet my very last dollar that the center is the positive. Otherwise 12v would be exposed on the connector.....

Once upon a time, in a far away land.... I had a boombox with 10 batteries.... 15v at full charge. I made up little discs and put the wire on one side of it for both the positive and negative. They sandwiched between the batteries and the contacts. Boom, never ending radio. Can't believe my dad let me do it........he probably didn't know.

[emm-dee]

Originally Posted by Larry-NC

Yes, that is a coaxial barrel connector. You need to make up a cord with a barrel connector (like on your wall wart) on one end and a cigarette lighter plug on the other end. The one I've linked will cost you the princely sum of 16 cents with free shipping. AND it includes a built-in fuse and on-off switch.

Here's an assembly already made up but I don't know if the barrel connector is the right size or whether the polarity is correct.

Unfortunately, the image of your device did not show the symbols that indicate whether the center is positive or negative, so you will have to measure your current supply and match it.

Or maybe just contact the manufacturer and ask whether they have a pre-made automotive supply cord for it.

Larry

Larry

Not my device. It’s the one the OP is working with. To determine which is the positive pin just plug the original converter in and use a voltmeter. Betcha it’s the center pin...never seen otherwise. I have three cameras and two Wi-Fi routers that all came with an AC to DC wall plug. Plugs are no longer needed.

Every device and system on my 3051 except the microwave and air conditioner is fully functional on 12 volt power.

[Larry-NC]

Originally Posted by 5picker

Sorry I wasn't more 'elegant'!
Geesh...

I was thinking this was going to be a regular transfer from home to trailer. Convenience and cleanliness of the installation count.

Also, this eliminates the chance of inadvertently connecting the clips in the wrong polarity in the dark/in a hurry/etc. and damaging the repeater.

(When I was designing modems, it was a rule that you could never be sure of the polarity of telephone jacks (-48 volts across red-green), so we always included a "polarity bridge" at the front end so the circuit would work on either connection. It is unlikely that this repeater includes one.)

Larry

[DaleV]

Originally Posted by emm-dee

I looked at the SureCall unit you’re talking about. It operates on any voltage between five and fifteen volts DC. You don’t need the brick...just a source for 12v which shouldn’t be a problem.

Look around the house and I bet you’ll find an old unused power supply that has a plug on the end of the cord that will fit the SureCall box. Cut it off and find a place to splice it into 12v in the motor home. I’m not familiar with the 2401 but looking at pictures makes me believe you can get power at the back of the Furion TV (Forester likes 12v TV sets) or on the other side pull the DVD/radio head and get 12v there.

My 3051 has factory installed 12 volt outlets at three locations. I use them to supply 12v directly to a Netgear router (for the rear camera), an amplified subwoofer and two 300 watt inverters used to power the AppleTV systems. Search around and you’ll probably find some on your unit.

Before you use a plug from another device, make sure the polarity is correct for the device you are wanting to use it on. It should say on the brick. It'll be something like in the picture. If you don't have the correct polarity, you could damage the device you are trying to power up.