Planing to use Victron lynx 1000A Shunt but can only find fuses up to 800A

[FilterGuy]

That is totally incorrect see my explanation above. I have one and so do hundreds of others. No, absolutely no shunt is fused for the loads or rated current flow. The only fused connection for ANY shunt is for the power lead to power the shunt itself.

The Lynx Shunt manual says the fuse is the main system fuse and gives this diagram



If you look at the pics in the manual, you can see the same:



And it says this about the fuse:

 

[FilterGuy]

This is simply a shunt in a form factor that will attach to the Lynx system. Current flow is not necessary across the red terminals. Voltage is necessary to power the shunt. All current flow is across the negative (black) only. It is installed on the end and not the middle so positive current can power the shunt itself but the entire 1000a bus current is not intended to flow through the Red lugs. The ENTIRE negative current must flow through the shunt (black lugs). It functions and is wired the exact same way as any other shunt.

Not using the positive side of the Lynx Shunt kinda defeats the purpose of the whole integrated lynx system.

 

[OzSolar]

This is simply a shunt in a form factor that will attach to the Lynx system. Current flow is not necessary across the red terminals. Voltage is necessary to power the shunt. All current flow is across the negative (black) only. It is installed on the end and not the middle so positive current can power the shunt itself but the entire 1000a bus current is not intended to flow through the Red lugs. The ENTIRE negative current must flow through the shunt (black lugs). It functions and is wired the exact same way as any other shunt.

6. Installation

www.victronenergy.com

By all means, please continue to demonstrate that you have no experience with this product. I won't get in your way again. I'm just here to help the OP.

A system with one of these will not work unless a fuse is installed.

Here's the pertinent page from your link.

 

[629658]

Not using the positive side of the Lynx Shunt kinda defeats the purpose of the whole integrated lynx system.

I didn’t say you didn’t use the positive it is used as a power source for the shunt itself. For instance in my installation this shunt would add on to the end of my Power Ins approximately where I installed a regular Victron Shunt. My negatives from the shunt would attach on the black lug. The positives from my inverter would attach to the positive buss of the Power In just like I have them wired. This shunt is no different than my Victron shunt and is wired the exact same way. Notice no positive is attached to the shunt. No big fuses and I went with the 500a shunt because my max inverted load or charge is 285 amps. You do as you wish but you will be unable to find fuses larger than 500 or do amps so that is your rate limiting factor. Mine would be my 500a shunt but they also sell it in 1000a shunt no fuses required.

 

[629658]

By all means, please continue to demonstrate that you have no experience with this product. I won't get in your way again. I'm just here to help the OP.

A system with one of these will not work unless a fuse is installed.

Here's the pertinent page from your link.

View attachment 131351

And your experience is? At least I own and use the product. Any suggestions on OPs question of how he retains 1000amps current flow through his buss? Crickets.

Per my instructions he retains his 1000 amps current and if he takes my other suggestion he could save himself $3-500.00 as a bonus.

 

[OzSolar]

And your experience is? At least I own and use the product. Any suggestions on OPs question of how he retains 1000amps current flow through his buss? Crickets.

Per my instructions he retains his 1000 amps current and if he takes my other suggestion he could save himself $3-500.00 as a bonus.

Oh my gosh. What's next with you? This doubling down thing you're doing is terribly unproductive and no one is even mentioning Sol-Ark. May I suggest that you look into some healthier hobbies? Perhaps lay off the drink just a bit? Buuurrp...

It's perfectly clear that your sole reason for being here is to pick fights with people. You'll have to work that out with your new therapist as I'm sure the last three or ten have made it pretty clear they can't help you.

None of your pictures show a Lynx Shunt, so again it's pretty clear you don't have experience with one.

To answer your question, I've installed a few dozen of the Lynx product family plus hundreds of other shunts but of course you're not here to learn, you're here to take embarrassingly shameful shots at ridiculing people who don't love Sol-Ark. Did I miss something?

 

[629658]

Yes you forgot to blame Victron for a faulty product just the usual

 

[629658]

So answer the original question and quit whining. How can you run a full 1000 amps through the Lynx Shunt?

 

[OzSolar]

Yes you forgot to blame Victron for a faulty product

We will all be here here waiting on the picture of YOUR lynx shunt.


Still waiting....too soon?

 

[629658]

Can’t answer figures. I clearly stated my components. I answered the Ops question and then you chimed in 10 posts no answer. At least I made some recommendations that will work. Must be tiring hijacking post to grind your ax.

 

[OzSolar]

So answer the original question and quit whining. How can you run a full 1000 amps through the Lynx Shunt?

Maybe your sponsor can help you? Remember, the first step is admitting you have a problem.

 

[629658]

Maybe your sponsor can help you? Remember, the first step is admitting you have a problem.

Projection as usual

 

[OzSolar]

Can’t answer figures. I clearly stated my components. I answered the Ops question and then you chimed in 10 posts no answer. At least I made some recommendations that will work. Must be tiring hijacking post to grind your ax.

What? Buurp...

 

[629658]

What? Buurp...

There is treatment for that

 

[OzSolar]

We will all be here here waiting on the picture of YOUR lynx shunt.


Still waiting....too soon?

And still waiting

 

[BillCaswell]

That is totally incorrect see my explanation above. I have one and so do hundreds of others. No, absolutely no shunt is fused for the loads or rated current flow. The only fused connection for ANY shunt is for the power lead to power the shunt itself.

I am still working to make sense about all of this.

This is from the Victron website.

• Lynx Shunt VE.Can - A positive busbar with a space for a main system fuse and a negative busbar with a shunt for battery
  monitoring. It has VE.Can communication for monitoring and setup with a GX device.

My interpretation is that the lynx shunt product has three functions:
1. Positive busbar (where my questions have been directed)
2. Negative busbar with a shunt for battery
monitoring
3. It has a VE.Can communication for monitoring and setup with a GX device

I've created a bit of a slide set to layout my understanding of how Victron explains their Shunt. From what I can see, it sits in the middle of the lynx distribution system. I am building this for a boat and need to follow the advice of my ABYC certified electronics engineer. He needs to sign off on the design for insurance purposes. For me this NOT about saving a few dollars, but doing it correctly.

BTW, these are pictures of the hardware siting on my desk.

 

[BillCaswell]

Sorry everyone. It looks like my post was redundant and late to the party. I had set up my reply and forgot to hit send. Only after hitting send did I learn about everyone else's posts. ughh...

 

[BillCaswell]

Charitable interpretation is they misunderstood the question.
Less charitable interpretation is they pretended to misunderstand the question.

The way to make this work is put a nickel plated copper stunt double in place of the shunt fuse.
The stunt double should be the same dimensions as the busbar.

Each battery should be fused as close as possible to the positive terminal.
Each branch circuit should also be fused at the distributor.
The fuse in the shunt is kinda pointless in a properly fused system anyway.
Especially in a 24 volt or higher system with LFP batteries.

I do not disagree. This application is for my boat. I'm working with an ABYC certified installer that happens to be an electrical engineer. The rub is that I need to use UL components and use an ABYC certified technician for insurance reasons. He happens to have used this set up on another boat, so suggested these components, without seeing the boat. It's not very expensive and when I priced other components separately they were more expensive. I totally agree that each power source needs its own fuse, along with each branch circuit. I am dealing with some space constraints so need to reasses the design anyways.

Thanks for the thoughtful reply.

I appreciate everyone's willingness to engage and share their input!

 

[629658]

I do not disagree. This application is for my boat. I'm working with an ABYC certified installer that happens to be an electrical engineer. The rub is that I need to use UL components and use an ABYC certified technician for insurance reasons. He happens to have used this set up on another boat, so suggested these components, without seeing the boat. It's not very expensive and when I priced other components separately they were more expensive. I totally agree that each power source needs its own fuse, along with each branch circuit. I am dealing with some space constraints so need to reasses the design anyways.

Thanks for the thoughtful reply.

I appreciate everyone's willingness to engage and share their input!

I think you have discovered a small flaw in this device. As I see it as currently configured the rate limiting factor is the central fuse.

1: So you can choose to put the biggest one you can find and keep some spares. Your current will be limited to your fuse size but no where near the 1000 amp rating.

2: You could fabricate a piece of bus bar to jump the lugs and eliminate the fuse altogether which would not jeopardize anything as you surely will have other fuses or breakers in place to cover your batteries and inverter. So this fuse is redundant and not necessary.

3: You could extend the two leads outside of the shunt install a T class fuse and holder which actually would increase your safety factor by a large margin.

4: You could rearrange the sequence of your equipment putting the shunt on the end instead of in the middle. This would work well as you wouldn’t be running all of your positive current through the shunt and it would just receive the voltage to operate the shunt.

5: You could eliminate the Lynx Shunt attach the Power Ins and the distributor together and add a Victron Smart shunt to the end (similar to what I did).

I think any of the above would be acceptable and pass inspection. I almost bought that shunt for a cleaner install but I was took cheap at the time. Now I am glad I didn’t. I know I mentioned this earlier but IMO the distributor is unnecessary for its cost. I was able to turn my Power Ins into distributors with a simple modification and saved myself several hundred dollars. I think if you want to utilize what you have I would personally choose option 3. It gives you real benefit and safety margin. Class T fuses are available for over 1000 amps and are far superior to MEGA fuses.

 

[629658]

I do not disagree. This application is for my boat. I'm working with an ABYC certified installer that happens to be an electrical engineer. The rub is that I need to use UL components and use an ABYC certified technician for insurance reasons. He happens to have used this set up on another boat, so suggested these components, without seeing the boat. It's not very expensive and when I priced other components separately they were more expensive. I totally agree that each power source needs its own fuse, along with each branch circuit. I am dealing with some space constraints so need to reasses the design anyways.

Thanks for the thoughtful reply.

I appreciate everyone's willingness to engage and share their input!

I think you have discovered a small flaw in this device. As I see it as currently configured the rate limiting factor is the central fuse.

1: So you can choose to put the biggest one you can find and keep some spares. Your current will be limited to your fuse size but no where near the 1000 amp rating.

2: You could fabricate a piece of bus bar to jump the lugs and eliminate the fuse altogether which would not jeopardize anything as you surely will have other fuses or breakers in place to cover your batteries and inverter. So this fuse is redundant and not necessary.

3: You could extend the two leads outside of the shunt install a T class fuse and holder which actually would increase your safety factor by a large margin.

4: You could rearrange the sequence of your equipment putting the shunt on the end instead of in the middle. This would work well as you wouldn’t be running all of your positive current through the shunt and it would just receive the voltage to operate the shunt.

5: You could eliminate the Lynx Shunt attach the Power Ins and the distributor together and add a Victron Smart shunt to the end (similar to what I did).

I think any of the above would be acceptable and pass inspection. I almost bought that shunt for a cleaner install but I was took cheap at the time. Now I am glad I didn’t. I know I mentioned this earlier but IMO the distributor is unnecessary for its cost. I was able to turn my Power Ins into distributors with a simple modification and saved myself several hundred dollars.

Here is a link

https://www.eaton.com/content/dam/eaton/products/electrical-circuit-protection/fuses/data-sheets/bus-ele-ds-1025-jjn.pdf

 

[jbryanwest]

After reading this whole string, I'm almost afraid to post, but have you looked at the specs on the 800A CNN fuse? This is the Little fuse time current characteristic curve. a 800A CNN from littelfuse will sustain 1,600A for 2 seconds, 1,400 A for 6 seconds and 1,200A for 100 seconds. Sounds like that would be within your initially described scenario.

Good luck, interested to hear what you end up with.

https://www.littelfuse.com/media?resourcetype=time-current-curves&itemid=78c06ee9-5ff1-464b-99ab-b3a828ca46c8&filename=fcc01-cnn-d