Community Forums

vegasmun · 09-04-2015, 04:28 PM

We leave our dog in our motorhome on occasion to go to dinner or see a movie. Twice now we have come home to find that we lost shore power. Fortunately on both occasions the dog was with us, as it was summer and the air conditioners weren't running and the inside temperature was close to 90 degrees. We have a 2800 watt sine wave inverter that keeps the refrigerator running but apparently not the air conditioners when shore power is lost. We have three air conditioner units, each at 15,000 btu. Is there a way to have the generator (10k Onan) automatically come on if shore power is lost, or would a larger inverter keep one of the air conditioner units running? We are nervous now to leave the dog if it's warm out and the air conditioner is necessary to keep her comfortable. Thanks for any help.

jacwjames · 09-04-2015, 04:49 PM

Depending on the inverter that you have there may be an automatic generator start function with loss of shore power. There could also be one that senses temperature.

I have a 7.5 KW Onan, it did not have these features so I installed a Onan EC-30W auto start. Below is a link to some information on it.

https://www.cumminsonan.com/autostart/faq/

This is a wireless system. Originally I had the Sensor/Display mounted next to the refrigerator ~20' from the front and it would loose communication. I have since moved it up and it is ~12' away from the front and seems to work better. It is best that the Sensor/Display unit be plugged into an outlet that is not powered by the inverter. The base unit is mounted above the generator on the firewall.

There is also a hardwired unit but I found the wireless unit easier to install and take with me if I get a new RV.

It will sense if the power drops out and if the temperature set point has been met the generator will start. I have the temp set point very low so that it will start every time the power drops.

I tested mine this last week, I had set the unit to Auto Start Mode, while we were breaking camp I flipped the 50 amp breaker off and after the set time (~2 minutes) the generator started. Naturally the AC units have to be on and set to AC.

wa8yxm · 09-04-2015, 05:14 PM

Can it be done: YES. in fact there is a line of generators designed to do just that.

I do not know anyone who sells an upgrade unit though.. I know Onan and Genrac both make controllers that can do it,,, But I do not know if they make them as an upgrade.

IF you have auto-generator start it would be fairly easy to modify it to make it do the job,, Only would take like 5 parts (or less) but I do not know anyone who makes the kit or a upgraded controller.

If you have AGS I can give you the plan easily enough.

shiggs68 · 09-04-2015, 05:27 PM

Onan makes a user installable Auto Start control.
https://www.cumminsonan.com/autostart/faq/

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vegasmun · 09-05-2015, 05:15 PM

Quote:

Originally Posted by jacwjames

Depending on the inverter that you have there may be an automatic generator start function with loss of shore power. There could also be one that senses temperature.

I have a 7.5 KW Onan, it did not have these features so I installed a Onan EC-30W auto start. Below is a link to some information on it.

https://www.cumminsonan.com/autostart/faq/

This is a wireless system. Originally I had the Sensor/Display mounted next to the refrigerator ~20' from the front and it would loose communication. I have since moved it up and it is ~12' away from the front and seems to work better. It is best that the Sensor/Display unit be plugged into an outlet that is not powered by the inverter. The base unit is mounted above the generator on the firewall.

There is also a hardwired unit but I found the wireless unit easier to install and take with me if I get a new RV.

It will sense if the power drops out and if the temperature set point has been met the generator will start. I have the temp set point very low so that it will start every time the power drops.

I tested mine this last week, I had set the unit to Auto Start Mode, while we were breaking camp I flipped the 50 amp breaker off and after the set time (~2 minutes) the generator started. Naturally the AC units have to be on and set to AC.

Jim, your response got me looking further into my owner's manual and sure enough I do have the auto start, and never realized it. I believe I have the hard wired version that you have. A couple questions please. A quick read and I didn't see what the defaults were for time and temperature, or how to change them. Also, when I break camp, do I switch from auto to manual, so that when I unplug from 50 amp service it doesn't do the auto start? Thanks!

MisterT · 09-05-2015, 05:32 PM

I typically leave our AutoGen start ON, so that I don't forget once we've left the valuable 50a or 30a service. I will say, tho, if you use it mostly for VOLTAGE, rather than temperature, then when your're driving it will not typically come ON.
I could see that it's useful, tho, for TEMP autostart since that may come into play when you lose 50a/30a power, or if you're drycamping with only 20amp service.

redhooker · 09-05-2015, 05:51 PM

On my coach the 50 amp system does not like shore power combined with genset- I believe I may have a condition where there is momentary open neutral. I would love to add this option but my only concern with auto start is does the transfer switch prevent the shore power, when it returns, from crossing the genset?

jacwjames · 09-05-2015, 06:28 PM

What type of Inverter and power management system do you have.

I have the Trace Inverter with the RC7GS display. I have auto start but the parameters that I can set are Time and Battery Voltage. I do not use these parameters.

I do not have auto start for loss of shore power or temperature.

I think that there is a method to add components to do this but I opted to go the Onan System which has worked well for me.

There is another system out there that does have the auto start for loss of shore power, I believe it is a Magnum system.

Read your manual, determine the make and model of your system and then start asking questions, possibly on a new thread.

Good Luck

jacwjames · 09-05-2015, 06:36 PM

RedHooker
Do you know what model Inverter and controller you have??

One thing I would do or have done is check your transfer switch. The system should work instantaneously. If your power is dropping out there may be a problem with the transfer switch, possibly loose connections.

Depending on the age of your system there was a transfer switch used in the ~2000 period of time that had lots of problems with overheating and failure. There was a recall done on this but as usual there are probably coaches that didn't have it fixed. The company eventually went bankrupt.

I believe the make model of the bad system was Iota ITS-50R, Monaco quit using these in Sept 2001.

My transfer switch is Esco (Lyght) LPT50BRD

Melmoses · 09-06-2015, 06:04 AM

I have a Xantrex inverter and it has the ability to do either low voltage or temp auto generator start. Only problem is, some folks found out it doesn't always work as stated. So to make sure my dog is protected if power is lost I installed the Onan EC-30w system. Now I leave the Xantrex set for low voltage and I am as sure as I can be that Jack is safe from heat.