Forum Discussion

Tom_Barb's avatar
Tom_Barb
Explorer
Nov 18, 2017

battery fuse

This week, we had a power outage here on the island due to high winds and heavy rain. We were out of power for about 5 hours. during this time we retired to the coach. While there we discovered that the inverter charger would not connect to the battery pack. We then used the Gen-Set. to power up, which it did as advertised.
The next day I discovered the main line fuse between the battery pack and the inverter was smoked, It had over heated and melted the entire fuse and holder. totally destroying it.

Our new Magnum inverter / charger control panel would show a low battery and shut down when the gen-set was shut down. while on 50 amp service (after power was restored) it looked normal. but would show the battery at 13.8 volts.

today I called Newmar to see if the fuse and holder was available, yes it is at 130 bucks.

the old fuse was not blown, just burned, the theory is, it had a loose connection which created a high resistance connection and heated burning the whole thing to ash.
  • scrubjaysnest wrote:
    Tom/Barb wrote:
    This week, we had a power outage here on the island due to high winds and heavy rain. We were out of power for about 5 hours. during this time we retired to the coach. While there we discovered that the inverter charger would not connect to the battery pack. We then used the Gen-Set. to power up, which it did as advertised.
    The next day I discovered the main line fuse between the battery pack and the inverter was smoked, It had over heated and melted the entire fuse and holder. totally destroying it.

    Our new Magnum inverter / charger control panel would show a low battery and shut down when the gen-set was shut down. while on 50 amp service (after power was restored) it looked normal. but would show the battery at 13.8 volts.

    today I called Newmar to see if the fuse and holder was available, yes it is at 130 bucks.

    the old fuse was not blown, just burned, the theory is, it had a loose connection which created a high resistance connection and heated burning the whole thing to ash.


    This is a very common failure for fuses and you are correct it is a high resistance connection that causes the failure.

    The best fix I have found is replace it with a breaker. These are readily available at any automotive parts store. If you want to stay with fuses then check out Blue Sea. They are more expensive of coarse.

    that sounds like a good idea food for thought and not expensive
  • Tom/Barb wrote:
    This week, we had a power outage here on the island due to high winds and heavy rain. We were out of power for about 5 hours. during this time we retired to the coach. While there we discovered that the inverter charger would not connect to the battery pack. We then used the Gen-Set. to power up, which it did as advertised.
    The next day I discovered the main line fuse between the battery pack and the inverter was smoked, It had over heated and melted the entire fuse and holder. totally destroying it.

    Our new Magnum inverter / charger control panel would show a low battery and shut down when the gen-set was shut down. while on 50 amp service (after power was restored) it looked normal. but would show the battery at 13.8 volts.

    today I called Newmar to see if the fuse and holder was available, yes it is at 130 bucks.

    the old fuse was not blown, just burned, the theory is, it had a loose connection which created a high resistance connection and heated burning the whole thing to ash.


    This is a very common failure for fuses and you are correct it is a high resistance connection that causes the failure.

    The best fix I have found is replace it with a breaker. These are readily available at any automotive parts store. If you want to stay with fuses then check out Blue Sea. They are more expensive of coarse.
  • Tom/Barb wrote:
    This week, we had a power outage here on the island due to high winds and heavy rain. We were out of power for about 5 hours. during this time we retired to the coach. While there we discovered that the inverter charger would not connect to the battery pack. We then used the Gen-Set. to power up, which it did as advertised.
    The next day I discovered the main line fuse between the battery pack and the inverter was smoked, It had over heated and melted the entire fuse and holder. totally destroying it.

    Our new Magnum inverter / charger control panel would show a low battery and shut down when the gen-set was shut down. while on 50 amp service (after power was restored) it looked normal. but would show the battery at 13.8 volts.

    today I called Newmar to see if the fuse and holder was available, yes it is at 130 bucks.

    the old fuse was not blown, just burned, the theory is, it had a loose connection which created a high resistance connection and heated burning the whole thing to ash.


    heres a 200 amp system for $13 or a more original ehd one for 64$

    https://www.amazon.com/KnuKonceptz-Bassik-Gauge-Line-Holder/dp/B06WRVM461/ref=sr_1_6?ie=UTF8&qid=1511015833&sr=8-6&keywords=200+amp+fuse+and+holder
    https://www.amazon.com/Go-Power-FBL-200-Class-Block/dp/B001539B60/ref=sr_1_8?ie=UTF8&qid=1511015833&sr=8-8&keywords=200+amp+fuse+and+holder
  • wa8yxm's avatar
    wa8yxm
    Explorer III
    You can get those "T" fuses at local electrical supply. though they may have to special order (took me 3 shops to find it)... Cost is less than you paid though

    I blew one a few years ago

    Oh the reason the Inverter's panel showed normal voltage et-al when the generator was running is because it was providing the voltage. not the batteries. And it was on the Inverter side of the blown fuse.

    Same as my RV when i "DIsconnect" the batteries the indicatgor light still shows them connected... IF I have shore or generator power