Remote Control for Inverter

[claychps]

Hi all,
  I just got a small 300w Samlex 12v inverter and installed it in my shed. It is for running my TV in the house and with my current panel/battery set up, 3-4 hours runtime is all I am running it for. Samlex doesn't produce a remote control for this small an inverter but I know I saw a DIY circuit somewhere that uses one of those off the shelf automotive remote controls to turn on the DC side of the inverter. Can anyone help me with this?

Thanks,
Robert

[ghurd]

" turn on the DC side of the inverter"
Don't do that.
The large caps on the DC input cause huge surge currents and it will mess up the works.

The Samlex is the long narrow version, with a rocker switch for On & Off?
This is what you need-
http://fieldlines.com/board/index.php/topic,129565.0.html

If it does not have a rocker switch, you need to get an inverter with a rocker switch.

Single channel remotes are kind of hard to find lately (at a cost below a 2 channel).
Be careful the remote is push on, push off.  Some of the ebay sellers can not clearly explain what their items do.
Be careful the remote does not take some kind of logic level Vcc, and output a logic level Vo signal.  Some remotes need quite a bit of "stuff" added to them to make them usable for 12V and a relay.  Just because it says "car" in the listing does not necessarily mean everything is not 5V.
Obviously I ebay purchased more than my share of them that that did not exactly do what it sounded like they would do.
G-

[Rover]

Ghurd
Although I never bought one off of ebay, I have bought em at (autozone, carquest etc). Before I got heavily into microprocessors, thats how I controlled some pumps etc. They are terribly simplistic typically a 2 or 4 channel, (key fob with a receiver block ) with the leads from the units being able to handle ~ 1 amp as a swtiched load (some had 10 amp ratings but regardless) 

Obviiously not enough for a 300W inverter , but I always used mine with a relay to switch the load. Am I wrong in thinking you could just use a 35 amp standard car relay attached to the leads ?  I never ran an inverter off it , but I can't see the problem with a small inverter being switched from a relay

I have a little 400W inverter  that I cut on and off from the DC side with a 50 amp switch, how much different ? 

The units I'm talking about actually come with complete diagrams (I think some even can with diagrams for using relays, as they market for lighting use on cars, (ground effects that kind of thing))

[claychps]

Thanks Glen,
  Yes the Samlex has a rocker switch and I appreciate the link to someone who did it. After thinking about it overnight, I'll probably just go out and turn it off manually. It was more for my wife during the day so she wouldn't have to go out and turn it on, but once I explain the current draw leaving it on all the time, she'll understand and do it. Thanks for being such a great help to everyone here and I'm sure in your real life also.

Robert

[ghurd]

Rover,
Those sparks when you first connect the battery cables to the battery still happen, they just happen on the contacts where you can not see them.
Using a tiny relay in parallel with the inverters on/off switch avoids all the complications of the sparks and cap surge current.

Robert,
It is easier than it looks to make it remote controlled.
The remote control's relay in paralleled with the rocker switch.  That's all there is to it.  Instead of the rocker switch making contact between 2 tiny wires, the relay does it.  The switch or relay is connected to 'stuff' in the inverter made to deal with the surges.
The only issue is if the rocker switch is lighted, which can be a bit confusing.  I don't think any of my small Samlexs have a lighted switch.

Some smaller inverters have a pretty substantial current draw when off.
I have a generic no-name ~300W-ish inverter that still takes 500ma when it is Off.  Substantial, when compared to a Red 400W Vector that only pulls ~350ma when it is On!
G-

[claychps]

Glen,
  OK, I'll give it a try. Would this set up work?                                                                                                                                                                 http://cgi.ebay.com/Dual-Mode-Remote-Control-System-1-Channel-Frequency-12V-/250637375136?pt=LH_DefaultDomain_0&hash=item3a5b26d6a0 

Robert

[ghurd]

That will work.
Will need to set it in "toggle mode".  Maybe just moving a jumper.
I never purchased one that came with any instructions at all.

I do not care for that type of remote (exposed button in my pocket), and prefer the type with the slide cover if it is going in my pocket.
Example, with no implication that one seller is any better than the other, ebay #200531563597.
Notice the more detailed info in that listing may apply to the one you linked to.  And it is $1 cheaper. 

It looks like you just need to get the switch out of your inverter and solder a wire on the 2 terminals that already have a wire (or 2) on them.
The 2 wires you added will go into terminals B and C, one wire in each terminal.
Then 12V + and - in the marked terminals.
That's all there is to it... usually.

I got in the habbit of only paying about $6 total.  This new crop of $20 units is causing me sticker shock.

I stumbled onto this one a second ago, a bit cheaper, US shipper, exposed button, but left what I typed above.  ebay #230392846210.

The last couple I bought were 2-ch MOM and need an external DPDT relay added to self latch.  Button A turns something On, button B turns it Off.
More complicated for a newbie, but maybe someone else will find it useful for their application.  Looks the same as ebay #140465557591, or "RF Wireless Electric Garage Gate Door Remote 2 Channel".  Still $6 total.
G-

[claychps]

Again thanks for all your time Glen. It sounds easy enough to hook up !

Robert

[claychps]

Hi all,
  I received the remote control that I referenced in the above post. I removed the on/off toggle switch from my 300W Samlex and connected a cable to the two wires coming off the PCB. I hooked in pos/neg to the receiver, the positive from the Samlex to common and the other to the N/O terminal. I had to put the jumper one slot over to put it in toggle mode. Pressed the transmitter button and the Samlex came on. Very simple mod. The other good thing is the transmitter came with a slide cover over the button in case anyone is worried about it activating accidentally, not like the picture in the listing.
  Thanks Glen for your help and Rover who replied !

Robert