Inverter Fusing

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scr0che

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Inverter installation manual specifies a 300A fuse - should I be using a Class-T fuse (e.g. a Blue Sea Fuse A3t (class T) 300amp) or will an ANL fuse be sufficient?

Also, reading around the subject, should I be fitting a Battery Isolator Switch between the battery and this fuse? Or does simply removing the fuse serve the same purpose?
 
I wouldn't worry about the type of fuse as an inverter failure will take out anything, Overloading it should bring up an error rather than blowing the fuse. I wouldn't add any additional bits to a 300 amp supply line as they would have to be massive and are additional point of failure.
 
scr0che said:
Inverter installation manual specifies a 300A fuse - should I be using a Class-T fuse (e.g. a Blue Sea Fuse A3t (class T) 300amp) or will an ANL fuse be sufficient?

Also, reading around the subject, should I be fitting a Battery Isolator Switch between the battery and this fuse? Or does simply removing the fuse serve the same purpose?
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ITYWF that it should be possible to isolate the battery without the use of tools. This means that fuse types you mention are ruled out as alternatives to a switch and that a switch must be easily accessible.
 
Does that mean I can use an ANL Fuse?

Does that mean I should be installing an isolating switch between battery and fuse? What does a typical installation have?
 
scr0che said:
Does that mean I can use an ANL Fuse?

Does that mean I should be installing an isolating switch between battery and fuse? What does a typical installation have?
Click to expand...

If you don't know how an inverter installation should be, should you be installing one ? The 240V electrickery coming out of it is same same stuff as your house electrickey, it will kill you or your crew/family/guests just the same.

However, to answer your questions, An ANL fuse or a Megafuse are both fine.

The information in post #3 is incorrect. There is no requirement to fit a switch "easily accessible" or otherwise. The fuse types mentioned are fine. You could, if you wanted to, fit a switch, but that would be unusual. If you do, fit it just after the fuse, so the fuse also protects the switch. Be very sure to fit one that is rated at the inverter max output, plus some, continually.

I would not fit a switch.
 
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scr0che said:
Does that mean I can use an ANL Fuse?

Does that mean I should be installing an isolating switch between battery and fuse? What does a typical installation have?
Click to expand...
You can use an ANL fuse
If no fuse type is specified its your choice

The switch should be located where it is easily accessible but as close to the battery as practical

IIRC the fuse should be within 20cm ( 8 ") of the battery

I would fit the fuse between the the battery and the switch , as close as possible to the battery . A battery terminal clamp mounted cube fuse may be a attractive option.
 
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VicS said:
You can use an ANL fuse.

If the swit

You can use an ANL fuse

The switch should be located where it is easily accessible but as close to the battery as practical

IIRC the fuse should be within 20cm ( 8 ") of the battery

I would fit the fuse between the the battery and the switch , as close as possible to the battery . A battery terminal clamp mounted cube fuse may be a attractive option.
Click to expand...

There is no requirement to fit an isolator switch. If one optionally fitted a switch, there is no possible reason to fit it "as close to the battery as practical".
 
VicS said:
Out of interest what inverter are you fitting and are you planning to connect its output to a shorepower system?
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OK its aVctron Phoenix I believe.
No probs but the quick installation guide shows neither isolation switch nor fuse ! :(
 
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going off fuse topic, sorry. I recently fitted inverter without fitting an isolator switch. Standing back and using it, it just didn't feel right. I have since added an isolator switch close to the inverter. Now it feels proper job... If it looks right.......
 
peterf said:
going off fuse topic, sorry. I recently fitted inverter without fitting an isolator switch. Standing back and using it, it just didn't feel right. I have since added an isolator switch close to the inverter. Now it feels proper job... If it looks right.......
Click to expand...
The original post implied that the connection was being made direct to the battery. It is my understanding that a battery should have an easily accessible isolation switch located as close to the battery as practical. That's one reason for fitting a switch but of course if the inverter connection is being made via an an existing isolating switch another is not necessary for that reason.

A second reason , which I belive applies to the inverter in question, is that some Victron inverters have a push button to turn them on which could be accidentally pressed leading to a dangerous situation if any work was being done on the output side. ..... The fuse could, and probably should, be removed before any work is done on the output.
Your local isolation switch makes safe isolation easy.

As you say it looks and feels right to have a local switch.

A fuse is needed to protect the wiring as well as the inverter ( I believe the inverter has no internal DC input fuse )

Edit
The smart inverters can also be operated by another user by Blue tooth. Another good reason for an isolating switch, although I understand there is a link which can be removed .
 
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Yes, the inverter is going 'direct' to the battery it will be located <1m from them. To come off the main battery isolator which is >5m away, and the cable to it isn't the 70mm I need to use, well, it would cost too much.

The inverter in question has no internal fuse for ac or dc hence the need for a fuse on the dc side, and a garage type consumer unit on the ac side with appropriate B20 breaker for my 2 socket radial circuit. Please correct me if I am wrong there.

I'll have a think about the isolator just for the inverter. I'm putting in a remote switch to it for on/off which should suffice. And yes, removal of it's own DC fuse would be done before any work on the AC side.
 
VicS said:
The original post implied that the connection was being made direct to the battery. It is my understanding that a battery should have an easily accessible isolation switch located as close to the battery as practical. That's one reason for fitting a switch but of course if the inverter connection is being made via an an existing isolating switch another is not necessary for that reason.

A second reason , which I belive applies to the inverter in question, is that some Victron inverters have a push button to turn them on which could be accidentally pressed leading to a dangerous situation if any work was being done on the output side. ..... The fuse could, and probably should, be removed before any work is done on the output.
Your local isolation switch makes safe isolation easy.

As you say it looks and feels right to have a local switch.

A fuse is needed to protect the wiring as well as the inverter ( I believe the inverter has no internal DC input fuse )

Edit
The smart inverters can also be operated by another user by Blue tooth. Another good reason for an isolating switch, although I understand there is a link which can be removed .
Click to expand...

You make out as if an isolation switch is some sort of requirement, it is NOT. If someone wants to fit one, they can optionally do so, but there is no requirement to do so.

Anyone working on AC systems where an inverter is fitted should be removing the fuse and putting it out of reach of anyone else likely to be onboard. Relying on an isolator switch that someone else could turn on is a recipe for electrocution. You're working away in the aft cabin, someone comes onboard and finds the kettle isn't working, turns the isolator on and you get electrocuted. This is why lockout kist for domestic/commercial electrical systems exist.

Electrical Lockout Kits | Lockout Kits | CEF
 
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