Hey all

So we overloaded our Axpert clone inverter one too many times and it kicked the bucket (currently in for repairs).
We purchased another one though and intend on running them parallel to increase our overhead.

Now what we would like to do is install some sort of overload protection on the inverter output.
The idea is to have something similar to a PV fuse as its fast blowing, this would basically limit the inverters output and should this be exceeded, the fuse would blow before the inverter overloads.

We have looked into the idea of using normal breakers but this wouldn't work as even a 20A breaker can surge up to 80A for 10 seconds before it trips.

 

What we do have is extra DC PV fuses and fuse holders, would this work for what we intend? DC fuses are preferable due to their nature of being fast blowing, creating a larger gap when they blow and ease of finding replacements.

Suggest you get a professional to look at your setup, you appear to be walking down a dangerous pathway - putting fuses in an AC circuit??

24 minutes ago, Pumba said:

Suggest you get a professional to look at your setup, you appear to be walking down a dangerous pathway - putting fuses in an AC circuit??

Well it isn't necessarily dangerous considering that fuses were used for many years before breakers.
Additionally most electrical equipment has an AC fuse installed.

Another example is all plugs in the UK have to by regulation have a fuse in the plug itself.

AC fuses aren't anything new, it just isn't widely used here in South Africa which is why it seems quite odd.

The main pro of using a fuse is that they tend to blow at their rated amount where as a breaker tends to trip 3 - 4 times its rated capacity.
ElectroBOOM actually has a video that touches on this. He put 100A through a 30A breaker and it didn't pop the breaker.

He went further to contact the supplier of his breaker and reported that :
60A load - It takes 10 - 50 seconds to trip
90A load - It takes 4 - 15 seconds to trip

 

The main pro of using a breaker is that you can just reset it where as using a fuse, it would require you to replace the fuse.

No, using fuses won't save you. It is necessary to look for the cause of the overload and solve it, or use electronic (fast) load current limiters. Increasing the power of your inverter can solve the problem, but without specialists, it will not be possible to solve the problem correctly.

I have exactly the same problem also on Axpert 5kva and I have sourced the problem. 

An unsympathetic wife. She wants the kettle on not knowing that the geyser is on at that time.

Quick blow fuse seems the only solution or divorce for me.

On 2022/04/17 at 1:47 PM, ChrisBe said:

I have exactly the same problem also on Axpert 5kva and I have sourced the problem. 

An unsympathetic wife. She wants the kettle on not knowing that the geyser is on at that time.

Quick blow fuse seems the only solution or divorce for me.

Do yourself a favor and have look at a LCR (load control relay). It is a very interesting piece of equipment. You get them in different A ratings.

EG: It works on a principle of if a circuit is drawing more than lets say 15 A, then it will disconnect another circuit. If your combined plug circuits pulls more than 15A, then the Lcr opens to cut the supply to the geyser, stove or what ever circuit you want to switch off for that time. After the plug circuit goes below 15A , there is a time delay and then the Lcr contact closes again. 

And it is a lot cheaper than a attorney. LOL

Edited April 18, 20224 yr by Vaal