Need a small breaker panel to finish Inverter Replacement

[bigbillsd]

I am looking for a small breaker panel that will take a 30amp main from my inverter output terminals and has room for at least 2 @ 20AMP breakers to protect the coach outlets. It needs to be surface mount and "pretty small" to fit into the inverter compartment area. The old inverter had two built in 20 amp circuit breakers for the output lines, the new higher capacity inverter does not have that feature so I need to protect those 120 volt circuits very close to those output terminals.

Here is a pic from the manual of the setup I circled the part in Yellow that is need to find a source to purchase it from.



-Bill

[mikestock]

You must be looking at the same situation I had when replacing a Xantrex MSW with a 2000 watt Xantrex PSW. Seems the MSW was made specifically for rv and had 2- 15 amp breakers built in. They don't make the PSW this way. I had enough room so I mounted a Square D box with two 15 amp breakers next to the new inverter.

The idea is to protect 14 ga. wiring down the line.

You could install two inline fuse holders with a supply of 15 amp fuses nearby. They would take up a lot less space and still protect the wiring down the line.

[Gdetrailer]

GordonThree wrote:
Eh, do it right and don't overload the circuit in the first place. Use a glass fuse holder if you need fast response and compact size.

MEH..

No one is going to INTENTIONALLY "overload" a circuit.

BUT ACCIDENTAL overloads like shorted cord that can get plugged in, or say the Romex gets damaged causing a short CAN HAPPEN.

The breakers AFTER the inverter are there for a REASON and were PART of the original inverter that the OP HAD to replace due to the original inverter going DOA.

While yes, one "could" use those push button thermal breakers or even glass fuses, one must ask themselves if it is truly a PROFESSIONAL way to go about it..

The true answer is NO.

No real electrician who is worth their salt is going to do what you suggested, that is a DIY hack job..

Even myself a long time Electronics Tech would never want to sign my name to those hack solutions..

I HAVE had to REPLACE those push button thermal breakers for a living, they DO have a rather LIMITED life and if they are loaded anywhere near the ratings they WILL eventually get a hair trigger..

Home breakers in a small breaker enclosure ARE the correct way to go..

Glad the OP decided to go that way, much neater, professional and if a breaker ever gives any trouble you can find them anywhere to get replacements.

[bigbillsd]

JFYI. The MS2812 is in and working great. Just used a two circuit sub panel as suggested and wired it up to jumper the 30amp to both legs then hooked up the two twenty amp circuits to the breakers.

Thanks for all the suggestions! Now am moving on to fishing a couple of cat 5 cables from the front to the rear of the coach.. that looks like lots of cramped spaces and probably plenty of blood letting to come!

[bigbillsd]

Old Duck wrote:
Just curious which Maganasine you are installiing. I'm working on installing a MSH3012. Good luck with your install.

An MS2812

[TNGW1500SE]

I see you only have 120 volts to the breaker. Most panels you'll find in stores are set up 240 volts.

If you want a 30 amp main and can't find a panel, just use a "Main Lug" panel (they're smaller) and don't feed the lugs. Feed the panel using a 30 amp breaker using one of the panels breaker slots and mark it as "main". Jump the lugs together so both bars have 120 volts.

[GordonThree]

Eh, do it right and don't overload the circuit in the first place. Use a glass fuse holder if you need fast response and compact size.

[Gdetrailer]

GordonThree wrote:
If space is really tight, mount two of these in a covered junction box:



20 amp push to reset breaker
Clicky

"Thermal" breaker.. :R

Not all that great, very limited trip life and presents some resistance.. Each time it breaks the circuit it gets weaker.. I would take a screw in Edison fuse any day over those cheap thermal breakers.

Do it right the FIRST time with a standard 2 position panel and NEVER ever have to do things over again.

[GordonThree]

If space is really tight, mount two of these in a covered junction box:



20 amp push to reset breaker
Clicky

[DrewE]

There certainly are panel mount 120V breakers. If you get a couple that are small enough, you could mount them to a blank coverplate in an outlet box (a handy box or similar). Depending on the breakers, it might not technically be up to code to do so, but it would not be especially unsafe. Probably the round pushbutton kind would be the easiest to mount (as making round holes in a coverplate is easier than making rectangular ones, at least with the tools I have).

If overloads are not a common problem, a couple of panel mount AGC fuseholders would also suffice.

If this were my project, I would just get a single or double position circuit breaker box such as has been already shown.

[Gdetrailer]

bigbillsd wrote:

westend wrote:


An alternative is to buy surface mount breakers and wire up the distribution from those. You can make it all look good by mounting the breakers on a piece of aluminum plate. Here's a good place to shop for circuit protection: Waytek Wire. Mounting three surface mount breakers will use about 1/8 -> 1/4 the space of a steel box. If you'll pay the price, the Cooper-Bussmann manual breakers are the way to go, they even sell a sealed Marine type (not necessary, IMO).

Do they make surface mount breakers for 120 AC current? Everything I looked at was automotive, mostly @12 volt.

ANY 120V or higher connection MUST be contained in some sort of enclosed box. IF you do find a "surface mount" type of 120V breaker you WILL need to put it into some sort of enclosure UNLESS it is specifically designed and rated for use outside of enclosure..

Not saying there is no such critter but there IS logical reasons why you are not seeing this type of breaker.

You might find a surface mount breaker in use in INDUSTRIAL controls but they too WILL need to be mounted in an enclosure. Most any industrial items like you seek WILL be far more expensive than simply buying a general purpose 2 position breaker panel I linked in my post above.

12V stuff IS NOT treated the same as 120/240 as far as electrical codes goes and those types of electrical connections are NOT required to be contained in an electrical enclosure..

[RollandB]

Just curious which Maganasine you are installiing. I'm working on installing a MSH3012. Good luck with your install.

[bigbillsd]

westend wrote:


An alternative is to buy surface mount breakers and wire up the distribution from those. You can make it all look good by mounting the breakers on a piece of aluminum plate. Here's a good place to shop for circuit protection: Waytek Wire. Mounting three surface mount breakers will use about 1/8 -> 1/4 the space of a steel box. If you'll pay the price, the Cooper-Bussmann manual breakers are the way to go, they even sell a sealed Marine type (not necessary, IMO).

Do they make surface mount breakers for 120 AC current? Everything I looked at was automotive, mostly @12 volt.

[Gdetrailer]

KD4UPL wrote:
You don't need a main. Your main between your power cord and inverter protects on shore power. Your inverter shut down circuits protect on inverter power. Is your inverter even capable of enough power to trip a 30A breaker?
If you really want one then get a 2 space breaker panel like the many that have been shown in this thread, install a "main" 30 in one slot and a tandem 20 in the other. Then wire the output of the main to the input lug of the other buss bar holding the tandem.

From the diagram the OP posted, the inverter was fed from the shore power breaker panel with a 30A single pole breaker.

That would mean that the input of the inverter acts as a 30A "UPS" and would have 10 ga wire from the RV breaker panel.

The output of the inverter (which acts like a ATS) was sending power to TWO different 20A circuits.

IF the OP does not add a small breaker panel to the output of the inverter (IE tie the two circuits together) and the output of the inverter does not exceed 20A (2400W) then the OP will need to DOWN GRADE the 30A breaker. The reason for that is the two 20A circuits from the inverter would be serviced with 12Ga wiring..

OP simply needs a small add on breaker panel, the smallest are "2 space" FOUR circuit boxes which can handle one double pole or 2 single pole standard size or 4 half size single pole breakers..

These panels do not have "main" breakers, instead they have INPUT LUGS.. Cost shouldn't be much more than $12 for the small panel..

Looks like this..



This one is 11" tall and 6" wide..

Found HERE

Takes standard easy to find breakers (but if you use two standard single pole breakers you will need to "jumper" the two lugs feeding the breakers from the inverter together).

Best bet is to go to the store and see what they have available, many times they have other versions than what is listed on the website. You might wish to check Lowes also if the panel at Home Depot is too large.

IF new panel will not fit where the old inverter was you can move the location of the new small breaker panel by using 10 ga wire from the inverter to the new breaker panel location.. That keeps things inline with the 30A breaker feeding the inverter.

[RoyB]

BLUE SEA PRODUCTS may have a small Marine Boat type circuit breaker for you... Might fit your needs better than the commercial wiring stuff...

Search on Internet... Buy from AMAZON

Roy Ken