Did you see the ad for the External “Soft Start”

Morich

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I admit to rarely reading most ads but this is one that caught my eye and thought I might point it out as something to look over?

https://camperreport.com/cool-summers-start-with-softstartup-the-must-have-rv-upgrade/

I know we have often had mention of the soft start to install on AC units but that puts it out for many. Especially the folks who don't want to climb on the roof?
This appears to be a single unit plug-in type like a surge protector so maybe a good fit for a wider market as it leads one to believe one unitl serves all AC units on an RV?
Maybe something to look over. I stopped before reading the price, so your choice from here!!! :D
 
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A hard start cap does practically the same thing, just in a different form. It cost much less too, about 1/10. Keep in mind this website sells soft-start devices.
https://www.briskheat.com/news-events/soft-start-vs-hard-start
This is an impartial assessment of both capacitors:
https://www.ecmag.com/magazine/arti...-start-are-soft-and-hard-start-kits-necessary
This explains the differences in a different way, with more detail.
https://www.coastalclimatecontrol.c...t?tmpl=component&print=1&layout=default&page=
Each individual must assess their situation are act accordingly.
 
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Richard that product or one like it by another manufacturer has been available for a few years now. There have been a few others looking for reviews on how it works but there hasn’t been a lot of comments on this.

I purchased two soft starts for my motorhome but my wife has requested that I stay off the roof. So, I hired a mobile tech to come to the house to install them. That happens next Monday.

I figure that I could save some money and install them myself but I have to agree with my wife that I’m not all that steady on the ground.
 
I had not seen the combined unit and begin to get flak about some of the things I want to do, so thought something that could just be plugged in might be just right for some folks!
I'm sure the item is going to be more expensive but it might be a tossup if we are looking at hiring labor!
Falling off the roof can get even more expensive, so there is that point!
 
There are all kind of question about how that device works with surge protectors and othe EMS devices. As to to cost would you believe $1200+ on sale for $795.
 
A head scratcher for me. A true soft start uses thyristors (pulse width modulation) to ramp up the voltage and current for a specific time period minimizing the initial surge. A soft start attached directly to the AC reduces voltage drops and current dips that would otherwise be felt by all other devices in the coach during start up.

This device is a current limiting device that will limit current to every device in the coach at the time of a startup surge. The principles of Ohms Law, and Kirchoff’s law still apply. Limiting current supplied to the entire coach will limit current to every branch circuit proportionally during an AC start up. I’m struggling to see the value in it.
 
Waiting for one to be delivered. Paid for it- but on long back order which has me concerned. If it works it will be a big help for us when we go to 30 amp only service locations. Hoping it meets needs of our 50 amp rig
 
A hard start will not reduce the 1/6 second 60 amp in-rush current when a electric motor with start and run windings goes from stationary to rotating. It may increase it as the function of a hard start is to give a older tired motor higher starting torque. The only way to get more torque is to have more current or higher voltage.

A soft start limits the in-rush current to about 24 amps but the 24 amps flows for a longer time (1/3 second). A soft start may cause problems if the AC compressor motor is not in good shape and is taking higher than original amount of torque to start up.

It is technically feasible to have the soft start current limiting in the RV power cord and not right on the AC unit. Mike Sokol has tested both kinds and both work as claimed.
 
Having installed hundreds of industrial soft starts and taught seminars on them. I can tell you without a doubt this device is not technically a soft start. By virtue of function it is a line current limiter.

The purpose of a soft start is to protect high inertia equipment from start-up damage, and to reduce power consumption & surges on start-up. A true soft start also protects circuits on the same feeder from momentary voltage dips and current deprivation through a controlled startup of the device itself.

This device will actually produce current deprivation onto every coach branch circuit by limiting all available feed current. Based on Ohms law, it may actually amplify the undesirable effects since the branch circuit demanding the most current (the AC startup) will momentarily steal from all other branch circuits what is made available via the line current limiting device.

OK so it may work with a generator or power pack, but at what long term cost? It is essentially inducing a brown out onto the entire coach for every AC startup. A hard wired AC soft start will actually eliminate the root cause of startup problems while protecting the AC unit itself and all other 120vac devices in the coach. I'll pass on this one.
 

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I have no dog in this fight and only mentioned it as something for the folks who have two AC and want to avoid the roof.
I don't like solid state things that are hard to find info on what and how they do things, so no opinion from me on good or bad as I have not found need for either type and that leads to a high level of "dis-interested"!
 
https://www.rvtravel.com/rv-electricity-hrdl-the-turtle/

This article has some pretty curves of what an AC draws when starting up and what it drops to while running, and how those curves are captured, for those geeks like me out there.

I have the Soft Start RV mounted in the AC housing right at the compessor and this is what it does. It makes a huge difference in the max current the AC draws when starting up. It lets me run my AC off a 3,000 watt inverter tied to my 400 AH Lithium Iron Phospate Battery Bank and 1500 Watt Solar Panel Array for a few hours. Enough to knock the heat and humidity out of the RV before bedtime.
 
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Looks like I have a new boat anchor or wheel chock

My new pedestal mounted Soft Start arrived and I have tried using it. Our 2016 Adventurer 38Q 50 amp hook up has quite an electric load with 2 heat pumps, a residential fridge, washer and dryer, convection microwave and a few other things to boot .(I knew from the beginning I'd never get them all to run)

I bought the Soft Start as from time to time we find ourselves limited to a 30 amp hook up but needing 2 a/c units and the fridge here in the hot southland.

I hooked it up on my 30 amp plug at home and it worked fine starting the 2 heat pumps with a good delay between the 2. It pulled abou 24 amps total at that point after the start ups. The inverter was pulling about 1 amp of that as it always does.

Since once the fridge is running it usually draws about 1-3 amps so I was hoping I could add it to the load with the remaining few amps af capacity . Unfortunatly at start up the fridge compresser must have drawn a good load and the entire system kicked off and then retstarted with a brown out warning and only 85 volts on leg 2 when it tried to kick back on. I shut down and reconnectd only the heat pumps. No fridge though.

Much to my surprise I thus learned the Soft Start will not make more electricity or amps!!! (Just kidding)

So now I know I can only use the Soft Start for only the 2 heat pumps when we need them and nothing else. Gotta figure out the fridge thingy though.

Probably wasn't a wise choice buying the Soft Start- a rather expensive experiment. Thinking of more and new uses for it?? (Wheel chiock maybe???)
 
Looks like I have a new boat anchor or wheel chock

My new pedestal mounted Soft Start arrived and I have tried using it. Our 2016 Adventurer 38Q 50 amp hook up has quite an electric load with 2 heat pumps, a residential fridge, washer and dryer, convection microwave and a few other things to boot .(I knew from the beginning I'd never get them all to run)

I bought the Soft Start as from time to time we find ourselves limited to a 30 amp hook up but needing 2 a/c units and the fridge here in the hot southland.

I hooked it up on my 30 amp plug at home and it worked fine starting the 2 heat pumps with a good delay between the 2. It pulled abou 24 amps total at that point after the start ups. The inverter was pulling about 1 amp of that as it always does.

Since once the fridge is running it usually draws about 1-3 amps so I was hoping I could add it to the load with the remaining few amps af capacity . Unfortunatly at start up the fridge compresser must have drawn a good load and the entire system kicked off and then retstarted with a brown out warning and only 85 volts on leg 2 when it tried to kick back on. I shut down and reconnectd only the heat pumps. No fridge though.

Much to my surprise I thus learned the Soft Start will not make more electricity or amps!!! (Just kidding)

So now I know I can only use the Soft Start for only the 2 heat pumps when we need them and nothing else. Gotta figure out the fridge thingy though.

Probably wasn't a wise choice buying the Soft Start- a rather expensive experiment. Thinking of more and new uses for it?? (Wheel chiock maybe???)

Read your reply and thought hmmmm...

I just bought the pedestal plug in module this week and had it plugged in to the 50 AMP shorepower pedestal which then connected to my shorepower line. Since my coach is 15 years old with a basement AC I thought adding this might reduce stress on the AC - because if I have an issue with it, repair/replacement might likely be a nightmare.

So I didn't notice anything the first few days but as the temps began to hit the high 80s the other day I noticed that may AC fan would kick on, but the AC would not. I would hear the familiar click (or some kind of sound I'e come to know) that told me the AC would kick on in a second - and then hear another click and the AC would not start but the AC fan would kick on.

After hearing this a couple of times I thought I would be tempting a disaster so I shut off coach power at the pedestal, disconnected the SoftStart - and re-connected my 50 AMP cable to the pedestal. AC runs as normal.

I have a 2010 Winnebago Journey Express 34Y with a on-board/inline Progressive Industries EMS-HW50C surgeguard.

Now I can't find the thread in the forum where I think I saw mention that Winnebago put a 'soft-start' like device in these older coaches. Was I dreaming I saw this?

I am well within the return period and I think I may do that.

Is there something I am missing in thinking about this situation?
Any insights or thoughts appreciated.

Brian
 

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