What type CB for refer/freezer?

Pat T · 11-12-2022, 12:46 PM

Planning an install of a new refer/freezer (Vitrifrigo 180). For DC power it says,
" Provide a 25 A thermal-magnetic breaker type remote voltage switch. The remote switch must disconnect both the poles of the battery." I have been unable to find such an item. Do you know of such an CB/switch?
I would think that using a single pole CB on the positive side would suffice? Am I correct?
Thanks.

Choices · 11-12-2022, 03:49 PM

Not sure why.
On my GB some of the breakers are Heineman, out of Canada.

You could just use two single poles also.

Look for used breakers. Easier to find.

jgwinks · 11-12-2022, 05:02 PM

Blue Seas has a double breaker that's essentially two breakers stuck together and a pin connecting the two levers. If one trips it takes the other with it. It's really meant as an AC main breaker but they are AC/DC rated and available in several amperages.
Not sure why they specify breaking both legs but there must be a reason.

Comodave · 11-12-2022, 05:31 PM

One problem may he that the negative lead may not go to the electrical panel. Lot of boats only have the positive lead going into the electrical panel.

Pat T · 11-12-2022, 06:22 PM

Quote:

Originally Posted by Choices

Not sure why.
On my GB some of the breakers are Heineman, out of Canada.

You could just use two single poles also.

Look for used breakers. Easier to find.

Thanks. I like the idea of using 2 breakers. Lots of choices out there. If there is a fault will both breakers trip?

jgwinks · 11-12-2022, 06:31 PM

Quote:

Originally Posted by Pat T

Thanks. I like the idea of using 2 breakers. Lots of choices out there. If there is a fault will both breakers trip?

Probably not, unless you pin the levers together. I set a pair up to do that once, I used a small bolt and nut, #6 as I recall. There are holes in the levers for the bolt.

Pat T · 11-12-2022, 07:04 PM

Quote:

Originally Posted by Comodave

One problem may he that the negative lead may not go to the electrical panel. Lot of boats only have the positive lead going into the electrical panel.

Another requirement per Vitrifrigo is that the 12 volt cables go directly from the refer to the battery. So nothing is going to a panel. The type of CB I need is something that I can mount in the engine room . That is where my batteries are and where the cables will be run. I think some call it a surface mount circuit breaker. Appreciate the input Dave .

jgwinks · 11-12-2022, 07:09 PM

The double breaker could still work, just have to put it in a box you can mount at the battery.

Pat T · 11-12-2022, 07:23 PM

Quote:

Originally Posted by jgwinks

The double breaker could still work, just have to put it in a box you can mount at the battery.

Ah yes. Just might have to do that. Hopefully they make a box for just a couple/few breakers. Not familiar but that's what the internet is good for.
Thanks again.

jgwinks · 11-12-2022, 07:25 PM

I'm pretty sure Blue Seas has a face plate for it, may have the box too.

https://www.defender.com/product.jsp...982&id=2428380

https://www.defender.com/product3.js...01&id=1239768#

Comodave · 11-12-2022, 07:27 PM

Since it is 12 volts it doesn’t need to be in a box. You could just use a piece of plywood or Starboard and cut out a hole to mount the breaker.

Pat T · 11-12-2022, 10:31 PM

Quote:

Originally Posted by jgwinks

I'm pretty sure Blue Seas has a face plate for it, may have the box too.

https://www.defender.com/product.jsp...982&id=2428380

https://www.defender.com/product3.js...01&id=1239768#

Excellent ! I knew somebody on this is forum would help. And yes, to make it simple they have the box for single or double toggle breakers. I'm half way done with this project thanks to you all.

jgwinks · 11-13-2022, 09:01 AM

Quote:

Originally Posted by Pat T

Excellent ! I knew somebody on this is forum would help. And yes, to make it simple they have the box for single or double toggle breakers. I'm half way done with this project thanks to you all.

No problem.

CarlF · 11-25-2022, 03:25 PM

I have a Vitrifrigo 180 and it was installed by the builder with a standard single breaker in the 12v panel. As, I'm sure, does everyone else. I can think of no good reason to protect the negative in a 12v circuit. Not required by either ABYC or EU regulations.

And connecting directly to the battery post is also wrong. It is likely to violate the ABYC rules for a maximum of 4 conductors on a post and creates a greater likelihood of a poor connection in the cable going to the busbar. Finally, ABYC requires circuit protection appropriate to the wire size within 7" of the battery post. Not sure how you'll get a breaker to do that so you'd have to install an additional fuse at the post.

Assuming that your breaker panel is wired with appropriate gauge wires for the load, I'd ignore the manual.

Steve DAntonio · 11-25-2022, 04:51 PM

Quote:

Originally Posted by Pat T

Another requirement per Vitrifrigo is that the 12 volt cables go directly from the refer to the battery. So nothing is going to a panel. The type of CB I need is something that I can mount in the engine room . That is where my batteries are and where the cables will be run. I think some call it a surface mount circuit breaker. Appreciate the input Dave .

I encounter a lot of VF's and I'm pretty sure I have never seen one wired directly to the battery, what if every equipment manufacturer required that? I suspect that requirement ensures fewer warranty claims for low voltage issues at the unit, but there is otherwise no good electrical reason to do this. A double pole breaker could be required on a vessel with an isolated ground DC system, found on many metallic vessels, and maybe VF got blamed for some corrosion issue so they cover themselves with this requirement, but it too is unusual, and I can think of no reason for it on a DC system, again other than those with isolated grounds. Can you share a photo of the page from the manual where it says this?

Most common toggle type, marine and household, breakers are thermal/magnetic. The electromagnetic trip mechanism responds instantly to high current surges, a dead short for instance, while the thermal portion uses a bi-metallic strip that responds to prolonged low level overloads.

CarlF · 11-25-2022, 05:31 PM

Quote:

Originally Posted by Steve DAntonio

I can think of no reason for it on a DC system, again other than those with isolated grounds.

Good thought on the isolated ground. Hadn't thought about that. Another theory I have is that some of these units are both DC and AC - and both voltages can be connected at the same time - the Vitrifrigo will use AC when available and then switch to DC when not. Perhaps the manual was poorly written (or translated) and confused the AC and DC breakers.

In any case, here's the paragraph out of my 180 manual for DC (the unit doesn't have the AC option). No mention of double breaker but still wants it connected directly to the battery post - as you say, a real problem if every manufacturer required this.

Cigatoo · 11-25-2022, 06:04 PM

I had voltage drop issues with our Danfoss fridge compressor. Was wired through a circuit breaker. Danfoss also wants their units wired directly to the battery. I used #8 wire and re- wired it directly to the house battery using one of these.
https://www.bluesea.com/products/502...Fuse_Block_Kit

Darlin · 11-25-2022, 07:29 PM

Wow, direct current to the battery could be a long run and will require heavy guage cable plus significant current loss. I gave up on DC refers long ago. I use a boat sized Whirlpool Arcos, made in Mexico AC refer with good results, I celebrated the day I trashed my old "Nevercold" Norcold a few years ago. The Arcos is connected to 3,000 watt house inverter and a 1,000 amp hour AGM battery bank fed by 900 watts of solar. Refer cost $300, You open the door and fog comes out. It makes ice fast and it is well lit inside. Easy and cheap to replace. Looking forward to Lithium upgrade this summer.

Pat T · 11-26-2022, 12:08 AM

Quote:

Originally Posted by Steve DAntonio

I encounter a lot of VF's and I'm pretty sure I have never seen one wired directly to the battery, what if every equipment manufacturer required that? I suspect that requirement ensures fewer warranty claims for low voltage issues at the unit, but there is otherwise no good electrical reason to do this. A double pole breaker could be required on a vessel with an isolated ground DC system, found on many metallic vessels, and maybe VF got blamed for some corrosion issue so they cover themselves with this requirement, but it too is unusual, and I can think of no reason for it on a DC system, again other than those with isolated grounds. Can you share a photo of the page from the manual where it says this?

Most common toggle type, marine and household, breakers are thermal/magnetic. The electromagnetic trip mechanism responds instantly to high current surges, a dead short for instance, while the thermal portion uses a bi-metallic strip that responds to prolonged low level overloads.

Here is the photo of requirements. Appreciate the comments. Good to know the CB I purchased is more than likely thermal-magnetic as it surely does not mention it in the description.

Pat T · 11-26-2022, 12:45 AM

Quote:

Originally Posted by CarlF

I have a Vitrifrigo 180 and it was installed by the builder with a standard single breaker in the 12v panel. As, I'm sure, does everyone else. I can think of no good reason to protect the negative in a 12v circuit. Not required by either ABYC or EU regulations.

And connecting directly to the battery post is also wrong. It is likely to violate the ABYC rules for a maximum of 4 conductors on a post and creates a greater likelihood of a poor connection in the cable going to the busbar. Finally, ABYC requires circuit protection appropriate to the wire size within 7" of the battery post. Not sure how you'll get a breaker to do that so you'd have to install an additional fuse at the post.

Assuming that your breaker panel is wired with appropriate gauge wires for the load, I'd ignore the manual.

Thanks for you input. I probably could have gotten away from using the double pole breaker but I did find one to use. Maybe an overkill but no harm. I think I am ok on the battery post connections. I have a house bank of 2 batteries and I don't think there are 4 conductors on each battery.

Did not know of the requirement for circuit protection within 7". I may have to add an additional fuse as you say. Damn, nothing is easy.

I would have liked to use my existing panel to tap power from to run this unit. The refer/fridge unit I took out of the boat was 240VAC so no luck there. If I chose to run new cables to the DC panel it would have added at least 10 more feet to my run. Connecting directly to my battery was the easier/shorter way and at that I am planning on using 8 gauge wire. Again maybe a little safety factor here but I can add small muffin fan for additional venting if needed with out worry.