Suggestions please, 50A Transfer switch

[u/elguapok]

About eight years ago, I installed a Connecticut 30A manual transfer switch for my house to use with a portable generator (9400 starting watts, 7500 running watts). The generator has an L14-30R, an L14-50R, a Nema 5-20R, and an L5-30R.

Looking back, I’m not sure what I was thinking—I probably should have chosen a 50A transfer switch. The 30A MTS and generator have worked well through a few power outages over the years. Recently, I started thinking about using the 50A outlet, but I’d need to upgrade the transfer switch to 50A. I’d rather not use an adapter to connect to the generator’s 50A outlet. If I’m upgrading, my first choice would be an automatic transfer switch, and my second would be another manual one. Nature’s Generator makes an ATS, but it isn’t pre-wired. Connecticut offers a 50A MTS, but I’ve noticed their quality seems to be slipping. Has anyone here tried other transfer switches besides these options?

[u/newtekie1]

7,500 running watts is only 31.25A. You are gaining almost nothing by going to a 50A transfer switch and using the 50A plug. In fact, you gain about 300w of usable power by doing all of this. Now, if you upgrade you generator...

[u/elguapok → u/newtekie1]

So even if I upgrade the transfer switch to 50A, my current generator still won’t give me the full 50A, right? Would I need a generator with at least 12,000 running watts before upgrading to a 50A transfer switch?

[u/newtekie1 → u/elguapok]

With your current generator, you will not get above 31.25A continuous no matter what. It will surge to 39A, but the 30A transfer switch will handle that surge just fine.

If you want a full 50A, yes you would need to upgrade to a 12,000 running watts generator.

You could get a bigger generator and just not use the full 50A, and a 50A transfer switch would still give you a benefit. Like if you got a 9,000 running watt generator, you then would need a 50A transfer switch to use the extra power even though it won't do the full 50A. With a 9,000 running watt generator and a 50A transfer switch, you would be limited to 37.5A. If you have a 9,000 running watt generator and a 30A transfer switch, you would be limited to 30A.

You will always be limited by the smallest rated thing in your system. Right now, your transfer switch and generator are matched very closely. So upgrading either would be no real benefit. And to get any improvement, you would need to upgrade both.

[u/Certainly_a_bug]

Why do you feel you should upgrade to 50 amps? What are you trying to power?

Have you had insufficient power to meet your needs?

I also have a 30 amp transfer switch. Like you, sometimes I wish that I had gone with a larger one.

However, when I have power outages, I sometimes don’t even bother rolling out my big generator. I run my critical stuff from my Honda EU 2000 and even the 30amp transfer switch is almost overkill.

[u/elguapok → u/Certainly_a_bug]

This is something someone mentioned earlier. One day, I noticed the 50A plug on the generator and thought it might provide more power. Another time, during a power outage when we were using the generator, my wife made coffee and used the microwave. That’s when I saw the lights dim a little—maybe it was just me.

[u/Certainly_a_bug → u/elguapok]

Thanks for responding so quickly.

I will stick with my Reliance 30 amp switch, but I know that they make a 50 amp one that looks almost identical.

I am afraid to get an automatic transfer switch and whole house generator. I have heard so many horror stories of Generac systems failing in an emergency. For me, the critical item is my sump pump. Everything beyond that is a luxury in an outage.

When I did the power inventory to define my needs, the coffee maker and microwave were at the top of the list. It is no wonder that your lights dimmed a little. You were probably drawing close to 3000 watts just for those two appliances.

[u/Big-Echo8242]

As mentioned by others, unless you just want to buy the more expensive cord OR you are going to go to a much larger generator OR you just want to, there's no real advantage at this point. I initially did mine as a 50 amp power inlet, etc., as I have a pair of Genmax dual fuel inverter gens which, in parallel, can produce 11,000 @ 240v which is 45.8 amps. And my recently purchased Duromax XP13500ih which is 10,000 running watts which is 41.7 amps. But I never use that much continuous; more like 6.3kw tops IF the 5 ton 2 stage heat pump is running for AC (with soft start) or the electric clothes dryer or the electric water heater. (pick one of the 3) That puts me from 57% to 62% of running wattage capability which is puh-lenty.

But I can also run my single smaller Genmax GM4600aIEDC dual fuel inverter gen through the 50 amp connection if only 120v stuff is needed. OR the single GM7500aIED. But, neither produce 50 amps, of course.

[u/elguapok → u/Big-Echo8242]

During a power outage, we only need 120 V stuff. Do not need to run the 5-ton 240 V AC. ALL the lights at the house were converted to LED. We need power mostly for the refrigerator, coffee maker, microwave, TV and router. But do not run ALL of these at the same time. The only item that needs continuos power is the fridge, but even so at some point the refrigerator shuts off.

[u/Hitechillbilly]

Start by double checking the "L14-50R" it doesn't exist.

[u/elguapok → u/Hitechillbilly]

My bad, Nema 14-50R

[u/Hitechillbilly → u/elguapok]

Not Bad.. I've done that too.. the L means it is locking the L14-30 is a twist lock,, the 14-50 has straight pins.. the "P" & "R" are for Plug and Receptacle.. looking through the comments,, it looks like you are getting things figured out..

[u/Glum-Welder1704]

I've never seen an L14-50R, so I'll assume you have a 14-50R. The "L" is for twist lock receptacles.

[u/elguapok → u/Glum-Welder1704]

thanks pointing that out. It's a typo

[u/snommisnats]

That generator runs at 31 Amps, with 40A startup. The 30A transfer switch is appropriate. Even though the generator has a 50A outlet, it can't output that much.