Portable generators with auto start capability.

Yes, when you lose the 120 shore power, you can trigger the gen somehow and no problem, but then the shore power 120 comes back on--you don't want to have 240v.

Or you could have a rig with two air conditioners--one on shore power only and the other on gen only

BFL13 wrote:
3tons (ISTR) has a Victron battery monitor of some sort that has a gen start feature you can set a voltage for. Not a clue how that works.

But if you had that connected to a converter that just lost its 120v input and thus showed a lower voltage (battery voltage) and that was what you had set as your gen start voltage, that could trigger the gen start?

EDIT More options on that

Can't link that Google article from Victron--anyway they have ways to do generator starting.

VICTRON GX STOP-START MANUAL

Doesn't really seem to be exactly what the OP was asking for, in a nutshell it is a BATTERY MONITOR with auto start. One would have to pull some tricks electronically to trigger it on shore power fail.. Then I don't see anything about 120V ATS so one would still need an ATS to switch between shore and gen..

3tons (ISTR) has a Victron battery monitor of some sort that has a gen start feature you can set a voltage for. Not a clue how that works.

But if you had that connected to a converter that just lost its 120v input and thus showed a lower voltage (battery voltage) and that was what you had set as your gen start voltage, that could trigger the gen start?

EDIT More options on that

Can't link that Google article from Victron--anyway they have ways to do generator starting.

GordonThree wrote:

CoeyCoey wrote:

I don't think I will need one of those. I am simply going to have a relay that closes when shore power is lost and tells the generator to start. Then the ATS will kick over to generator power.

A simple relay is not sufficient. you'll likely damage your generator, inverter, air conditioner, etc.

You AT LEAST need a time delay relay, one that for example waits to energize 2 minutes after power is lost, and stays energized at least fifteen - thirty minutes after utility power is restored.

The Magnum AGS isn't very expensive, and likely Victron makes a similar unit for their inverter. Far easier than trying to DIY some sort of time delay circuit.

Time delay, yes, however the time you quoted however may not be true for ALL ATS. A COMMERCIAL/INDUSTRIAL ATS with automatic gen switchover perhaps you MIGHT see such long delays in switchover and 15-20 minutes of gen run after commercial power is restored.

In reality that long gen run after commercial power restored is to allow the gen to operate WITHOUT A LOAD in a cool down cycle or allow for intermittent utility power . Even in this situation the power would have been transferred SECONDS after utility power was restored.

In reality, the ATS should only switchover at the ZERO switching point of the incoming sinewaves, just takes a few seconds for both sources to present this opportunity.

Some ATS do monitor the zero switching and some do not.

RV ATS just uses a small time delay to allow gen to come up to voltage and stabilize..

Per Progressive Dynamics 30A RV ATS HERE..

"Description of Operation

When the shore power is applied the relay is at rest and power is transferred to the panel.

When Generator power is applied there is a 20-45 second delay and then the relay activates transferring Generator power to the panel.

If shore power returns while the Gen power is present nothing will happen. When the Gen power is removed the relay will drop out and allow the shore side to supply power.

Generator overrides shore power. "

As far as the OPs request, I suspect you will have to "bake your own" custom gen start, ATS and gen shut down. You would have to add in lockouts (failsafes) in case gen fails to start within x amount of tries, protections for gen malfunctions like too high voltage, to low voltage, out of spec frequency, overloads and so on..

Most auto start/ATS systems are custom designed for a specific brand of BUILT IN gen and will have a lot of failsafes diagnostics baked into it..

I suspect at the end of the day, this is not your typically DIY project and will be more difficult and not to mention more expensive that it will be worth..

Perhaps try a different approach, you could go with a smart home T stat (in this use would not need to be connected to heating or cooling system, just needs some power), a mobile hotspot all run from your 12V system, setup the T stat to report the temp.. The if the power fails and your RV starts getting warmer then the smart T stat can send you an alert to your phone to let you know it is hotter than your preset..

RV should stay at a fairy reasonable temp for an hr or so without power provided you have it set in some shady spot.

Some inverter/charge/auto transfer units, Samlex EVO for example, have a generator starter output built in.

From page 74 EvolutionTM Series Inverter/Charger Owners Manual

4.7 AUTO GENERATOR START / STOP

Auto Generator Start / Stop function has been provided using “Common” and Normally Open “NO” contacts

of Status Relay (14, Fig 2.1). The relay is SPDT Type with contacts rated at 3A, 125 VAC / 30 VDC. Appropriate
external Generator Auto Start / Stop Module will be required for using this function.

GordonThree wrote:

pianotuna wrote:
GordonThree,

The Magnum hybrid inverter/charger does have a time delay built in when shore power is applied. I'm guessing the Victron does as well.

I would not purchase Magnum but would look at both Victron and Outback.

That delay isn't useful.

If the power isn't sure it wants to go out but instead waffles back and forth, I wouldn't want my generator restarting every 30 seconds.

Maybe outages are different in other countries? I've never experienced an unexpected outage the power just shut off and stayed off for an extended period. There has always been some waffling first.

The ATS has a delay built into it.

pianotuna wrote:
GordonThree,

The Magnum hybrid inverter/charger does have a time delay built in when shore power is applied. I'm guessing the Victron does as well.

I would not purchase Magnum but would look at both Victron and Outback.

That delay isn't useful.

If the power isn't sure it wants to go out but instead waffles back and forth, I wouldn't want my generator restarting every 30 seconds.

Maybe outages are different in other countries? I've never experienced an unexpected outage the power just shut off and stayed off for an extended period. There has always been some waffling first.

GordonThree,

The Magnum hybrid inverter/charger does have a time delay built in when shore power is applied. I'm guessing the Victron does as well.

I would not purchase Magnum but would look at both Victron and Outback.

CoeyCoey wrote:

I don't think I will need one of those. I am simply going to have a relay that closes when shore power is lost and tells the generator to start. Then the ATS will kick over to generator power.

A simple relay is not sufficient. you'll likely damage your generator, inverter, air conditioner, etc.

You AT LEAST need a time delay relay, one that for example waits to energize 2 minutes after power is lost, and stays energized at least fifteen - thirty minutes after utility power is restored.

The Magnum AGS isn't very expensive, and likely Victron makes a similar unit for their inverter. Far easier than trying to DIY some sort of time delay circuit.

KD4UPL wrote:
There are many portable generators available that allow for an remote start. The problem is they are mostly louder generators, not the nice quiet inverter models. Most of Honda's entire line, for instance, has this feature. You'll need the matching wiring harness and probably a generator controller. Portables often use a 3 wire start system of which there are 2 different versions. They are unlike home generators that usually use a 2 wire start system. (of which there are also 2 versions).
Magnum energy makes a decent stand-alone Automatic Generator Start (AGS). If you happen to already have a Magnum inverter in your RV then you can use the network AGS. Schneider conext makes an AGS too but it will not operate "stand alone". But, again, if you happen to have a Schneider/Conext/Trace/Xantrex inverter in your RV you could use it.
There are other companies that make stand alone AGS boxes but I haven't had good luck with them in the past.

Yes, I am seeing that several of the smaller and more quiet portables might have remote start, but no auto start feature. Larger ones do. I think I will probably go with the AIM generator as it is portable, very quiet at 58db, and has the features built in that I am seeking. Should save me some money by not having to buy and wire in an AGS.

I am going to Victron because of their power assist feature. Some of the Magnums have it as well, but Victron seems to have more features for a lower price and better integration with their solar controllers.