Community Forums

edwardvan00 · 12-07-2022, 08:23 PM

As a related message sent to Mike Sokol,
I’m interested in the SoftStartRV that I was discussing with a friend to replace a Surge Guard 34750 (EMS) that got zapped during a lightning event near our home and while the RV was plugged in at the house. The SoftStartRV-30A he mentioned was to run 2 A/C at once with a 30A shore power connection, which may be nice on occasions when only 30A is available.
I’m wondering if there is a 50A version that can substitute simultaneously for an EMS (Energy Management System) as well as a SoftStart for the 3 ea. 15K BTU units on the roof of the RV. This would consolidate the EMS shore power need and softstart ideal for times when there is only 30A shore power.

I’m also wondering if my Surge Guard 40250-RVC has EMS monitoring built in, thus no need for power condition monitoring at the shore power pedestal. Trying to solve EMS, Soft Start and Surge Suppression at the pedestal, all in one device before I buy a new EMS.

Jim_HiTek · 12-08-2022, 06:09 AM

Not sure you'd be able to run 3 AC's even with soft start for long as the run current is as much as 8 amps each, so 24 amps. Most RV parks equipment would melt their or your connectors. Or the breaker would repeatedly pop.

corvetteSS · 12-08-2022, 06:45 AM

Quote:

Originally Posted by Jim_HiTek

Not sure you'd be able to run 3 AC's even with soft start for long as the run current is as much as 8 amps each, so 24 amps. Most RV parks equipment would melt their or your connectors. Or the breaker would repeatedly pop.

Not sure if you can run 3 units, but last I checked 24 amps is less than 30 amps.. I use 29 amps continuously and have never seem anything melt. If you have, someone must have wired it wrong. So don't worry about anything melting (if your connections are good)

**hamm2018** · 12-08-2022, 06:56 AM

Quote:

Originally Posted by edwardvan00

As a related message sent to Mike Sokol,
I’m interested in the SoftStartRV that I was discussing with a friend to replace a Surge Guard 34750 (EMS) that got zapped during a lightning event near our home and while the RV was plugged in at the house. The SoftStartRV-30A he mentioned was to run 2 A/C at once with a 30A shore power connection, which may be nice on occasions when only 30A is available.
I’m wondering if there is a 50A version that can substitute simultaneously for an EMS (Energy Management System) as well as a SoftStart for the 3 ea. 15K BTU units on the roof of the RV. This would consolidate the EMS shore power need and softstart ideal for times when there is only 30A shore power.

I’m also wondering if my Surge Guard 40250-RVC has EMS monitoring built in, thus no need for power condition monitoring at the shore power pedestal. Trying to solve EMS, Soft Start and Surge Suppression at the pedestal, all in one device before I buy a new EMS.

In September we just had 3 Soft Starts installed when we had solar installed. A Soft Start is installed on each AC Unit to assist in a lower starting amp so you can run the AC Units on 30-amp service. In our case, on our solar power.
A Soft Start needs to be installed on each of the AC unit, one Soft Start will not control all of the AC's.

rssnape · 12-08-2022, 07:31 AM

I think that you are confusing the soft start for each air conditioner with a surge guard.
While if you put a soft start on each air I doubt that you will be able to run 3 on 30 amps. The last air that tries to start (even with soft start) will likely put the load over the 30 amps total and may trip the breaker.
You may fair better to keep two airs running constantly than having 3 cycling on and off with the higher load at start up.

Mudfrog · 12-08-2022, 08:13 AM

Quote:

Originally Posted by corvetteSS

Not sure if you can run 3 units, but last I checked 24 amps is less than 30 amps.. I use 29 amps continuously and have never seem anything melt. If you have, someone must have wired it wrong. So don't worry about anything melting (if your connections are good)

More times than not, something is going heat up if trying to run a continuous 29 amps through a 30 amp pedestal at most parks. Your connections may be ok but there's a good chance the park's (between the transformer and pedestal) isn't up to par. I think you've just been lucky..

OP, I'm not sure they make a whole camper soft start device. As others have mentioned, the ones I've read about get used on separate a/c units.

Capacitor · 12-08-2022, 08:21 AM

The op may be referring to this:
https://softstartup.com/products/

edwardvan00 · 12-08-2022, 04:53 PM

https://softstartup.com/products/

Exactly the item I was referring to, except what is you wanted to connect a 50A EMS monitoring device and still have the proposed SoftStart capability, not necessarily running all 3 A/C at one time. Trying to satisfy a one and done, EMS, Softstart, and Spike Suppression solution to have thorough power management.

F4Gary · 12-08-2022, 05:17 PM

Why don't you just call Soft Start and ask them?

I10 · 12-08-2022, 05:39 PM

Keep in mind if your thinking about purchasing a soft start or one of there thermostats. Now is a great time as they have 15% off by using code Cmeasy15. Its good till Dec10.

tngengineer · 12-14-2022, 07:37 PM

I believe the soft starts being sold for RVs use NTC resistors across the line to limit in-rush current. The better ones use a relay and timer to switch out the NTCs after a couple seconds of operation to limit wear and tear on NTCs and power losses.

You need a separate soft start for each AC. They won't limit in-rush after about 0.2 seconds of having power applied to their terminals.

I've designed such a soft start, bought components for a total of three units for my coach. They would get control power for the timer and relay from the 12vdc present at the control box within the roof unit. Therefore they would be simpler than store bought units, but every bit as reliable, probably even more so. The problem for me is the quality parts I have cost about $60/unit (from Mouser), not including an enclosure.

Yesterday, I came across https://www.ebay.com/itm/5000W-Power-Amplifier-Soft-Start-Board-High-power-Isolation-Transformer/374223455562?pageci=20be483f-7ac1-4a61-9e1b-cf7897908c4f&redirect=mobile on ebay and ordered three. These are designed to operate at 220V, not 110V and will likely require some modification to work on 110. The price was too good not to give them a try. They definitely have sufficient capacity and I suspect they have as good quality components as the brand name RV soft starters that cost a small fortune.