mini lite 2205s WF-5110rs 1000w inverter fuse question

[EvilBatmanKirk]

I have been trying to figure out if there is supposed to be DC side fuse between the battery bank and the factory installed WFCO wf-5110rs 1000w inverter. I cannot find a specific DC fuse recommendation in the WFCO manual or on their website but everything I have read about electricity/fuses/inverters says there should be one specifically a Class T slow blow 110amp fuse. I know the inverter has an integrated AC fuse/circuit breaker.

I recently completed the rewire and upgrade of the solar setup (following the national codes) and I never came across a dedicated DC side fuse for the inverter. I also did not find an inverter ground to chassis wire despite there being a ground hook up site on the back of the inverter. Additionally I found 2/0 AWG wire jammed into the inverter battery connections. Fixed those two problems. Afraid to use the inverter until my fusing concerns are resolved. My battery bank is 12v, wired in parallel, so no naughty stuff on my part.

Question- Should I go ahead and install the Class T slow blow 110amp fuse - DC side?

[Larry-NC]

Originally Posted by EvilBatmanKirk

I have been trying to figure out if there is supposed to be DC side fuse between the battery bank and the factory installed WFCO wf-5110rs 1000w inverter. I cannot find a specific DC fuse recommendation in the WFCO manual or on their website but everything I have read about electricity/fuses/inverters says there should be one specifically a Class T slow blow 110amp fuse. I know the inverter has an integrated AC fuse/circuit breaker.

I recently completed the rewire and upgrade of the solar setup (following the national codes) and I never came across a dedicated DC side fuse for the inverter. I also did not find an inverter ground to chassis wire despite there being a ground hook up site on the back of the inverter. Additionally I found 2/0 AWG wire jammed into the inverter battery connections. Fixed those two problems. Afraid to use the inverter until my fusing concerns are resolved. My battery bank is 12v, wired in parallel, so no naughty stuff on my part.

Question- Should I go ahead and install the Class T slow blow 110amp fuse - DC side?

Seems like you would definitely want a fuse or circuit breaker between the battery bank and inverter, to cover the case of a short within the inverter itself. (An overload on the AC side is covered by the integrated AC breaker.)

A fuse would be sufficient, but a breaker provides an easy means to isolate the inverter from batteries when stored, to eliminate battery drain via leakage in the inverter when storing. Here's an inexpensive example.

[EvilBatmanKirk]

Thank you for confirming my concern about needing a fuse and the breaker recommendation.

[JimM2109S]

Note this is a different model - a 2022 2109s. If not the same path used in your model, it may give you some ideas on where to look.

Inverter positive wire runs up and over pass thru storage compartment, down behind panel hiding water heater, thru floor into underbelly, out front of frame to battery disconnect switch at nose of tongue, back to a 100a circuit breaker on the left side of tongue, into battery box.

Inverter negative wire runs same path as positive until it exits the front of frame and terminates at a grounding screw on left side of tongue right next to that 100a circuit breaker.

[jimmarako]

This schematic is from Rockwood for their mini lites. If that mini breaker exists on your trailer I think your good to go. But then I'm not an expert so who knows.

Jim M.

[PhilFromMaine]

Originally Posted by EvilBatmanKirk

I have been trying to figure out if there is supposed to be DC side fuse between the battery bank and the factory installed WFCO wf-5110rs 1000w inverter. I cannot find a specific DC fuse recommendation in the WFCO manual or on their website but everything I have read about electricity/fuses/inverters says there should be one specifically a Class T slow blow 110amp fuse. I know the inverter has an integrated AC fuse/circuit breaker.

I recently completed the rewire and upgrade of the solar setup (following the national codes) and I never came across a dedicated DC side fuse for the inverter. I also did not find an inverter ground to chassis wire despite there being a ground hook up site on the back of the inverter. Additionally I found 2/0 AWG wire jammed into the inverter battery connections. Fixed those two problems. Afraid to use the inverter until my fusing concerns are resolved. My battery bank is 12v, wired in parallel, so no naughty stuff on my part.

Question- Should I go ahead and install the Class T slow blow 110amp fuse - DC side?

Many inverters have internal dc fuses in the unit. My Giandel says that there is no need for a fuse between the battery and the inverter because of said internal fuse.

Having said that, just about every DIY system I have ever seen has a circuit breaker (fuse) just off the battery between the battery and the inverter. I placed one (200 amps for 2200 inverter) on my set up. It can't really hurt anything and it certainly is easier to reset than a fuse. For a 1000 watt inverter you would probably want, in my opinion, a 100 amp circuit breaker. (That is 1000w/12 volt* 1.25= 104 amps)

My unit calls for a ground wire that leads back to the negative battery terminal. This is obviously for some sort of protection in case the metal case gets electrified (their words not mine). I am not exactly sure what sending 120 volts back to the battery would look like?

[TitanMike]

Originally Posted by PhilFromMaine

Many inverters have internal dc fuses in the unit. My Giandel says that there is no need for a fuse between the battery and the inverter because of said internal fuse.



Having said that, just about every DIY system I have ever seen has a circuit breaker (fuse) just off the battery between the battery and the inverter. I placed one (200 amps for 2200 inverter) on my set up. It can't really hurt anything and it certainly is easier to reset than a fuse. For a 1000 watt inverter you would probably want, in my opinion, a 100 amp circuit breaker. (That is 1000w/12 volt* 1.25= 104 amps)



My unit calls for a ground wire that leads back to the negative battery terminal. This is obviously for some sort of protection in case the metal case gets electrified (their words not mine). I am not exactly sure what sending 120 volts back to the battery would look like?

That internal fuse they say is all that is needed does nothing to prevent damage should the positive wire from the battery get shorted in any manner.

Best practice is to place a fuse or circuit breaker close to the source to protect the wire.

Manufacturers often cause serious head scratching when they make statements like for your Giandel.

Sent from my SM-N950U1 using Forest River Forums mobile app

[EvilBatmanKirk]

OK, I guess I should have mentioned I spent days, truly days, studying the factory wiring from the tip of the hitch right up to the converter/charger (even dropped the belly as I have plans there for next summer), with much help from 18LT (thank you sir - again), made lots and lots of diagrams for reference, and then: upgraded batteries to 3 Battleborn heated lithiums installed in the storage compartment, added 2 more solar panels, rerouted solar panel wires to storage compartment, removed the pwm controller from the system, installed MPPT controller & battery monitor in storage compartment, made a solar panel cut off switch, upgraded all cables, added busbars, fused every component as per manufacturer recommendations, added a Central disconnect switch, kept the chassis ground, kept the power wired out to hitch, relocated the factory DC switch (so I could actually get to it), removed the solar side from the factory DC switch, upgraded the solar on the side wires, installed a MPPT controller for the solar on the side wired directly to batteries, replaced converter main board assembly, created a separate 12v power center with a cut off switch for my 12v TV, DVD player, USB and 12v socket charge sites.

Most importantly - in regards to my initial posting/question I moved the inverter positive and negative 2 awg cables to busbars (negative chassis ground on negative bus) (fuses to the positive side bus). I have read that darn inverter manual like 10 times! It states a class t slow blow fuse is required - it does not say placement between the battery and inverter (DC side) and that the inverter has integrated fusing - but does not say 'for AC side'. I found it vague and confusing. On top of that I could not find a dedicated factory installed, inverter, DC side fuse. This is where I need to thank TitanMike and jimmarako for reminding me of what I consider to be the 'crazy mess of fuses with convoluted wiring' on the front part of the trailer frame. I guess somewhere in that setup is the rockwood version for the inverter DC fuse. That all said, a fuse is obviously needed. DC side fuse. (I found the forest Slow blow fuse is not a problem in my mind and Class T is the way for me. I have calculated the correct fuse amps needed and my inverter will never need to provide large amounts of amps for appliance 'start up' (and the inverter can't anyway). Thank you all for putting me back on track - I get lost in my head quite frequently.

[PhilFromMaine]

Originally Posted by TitanMike

That internal fuse they say is all that is needed does nothing to prevent damage should the positive wire from the battery get shorted in any manner.

Best practice is to place a fuse or circuit breaker close to the source to protect the wire.

Manufacturers often cause serious head scratching when they make statements like for your Giandel.

Sent from my SM-N950U1 using Forest River Forums mobile app

The issue in some cases is that the battery wire to inverter is extremely short and it isn't very easy getting a breaker installed in that short of a run. The fuse-breaker is ostensibly to protect the wire so conceivably you could only be protecting a 4-6" run. I installed a breaker on mine and it was ridiculously hard installing it using a thick gauge wire.

[18LT]

Did someone mention my name?
My camper's system is always changing. As a for instance, everything related to the batteries, inverters and solar charge controller is all in my basement, leaving a bunch of wires dangling in the passthrough compartment.
I sure hope I remember where all those wires go.

[Richard Dietzen]

Originally Posted by 18LT

Did someone mention my name?
My camper's system is always changing. As a for instance, everything related to the batteries, inverters and solar charge controller is all in my basement, leaving a bunch of wires dangling in the passthrough compartment.
I sure hope I remember where all those wires go.

Been looking in the wrong place and only seeing this now that 18 LT, your batteries are the kind that have low temperature cut off, right?

[18LT]

Originally Posted by Richard Dietzen

Been looking in the wrong place and only seeing this now that 18 LT, your batteries are the kind that have low temperature cut off, right?

My two 100-amp-hour lifepo4 batteries have low-temperature cutoff but my 300 amp-hour lifepo4 battery does not.

[Bob K4TAX]

While the inverters I have both have internal DC fuses. With a 100 amp demand and a fuse resistance of 0.005 ohms (5/1000) the voltage drop is 0.5 volts. To avoid this, internal to most inverters, they place two 50 amp fuses in parallel which cuts the voltage drop.

My concern with adding an external fuse or breaker is that it adds resistance to the circuit. In a high current environment, the small resistance adds to voltage drop.

Bob

[18LT]

Originally Posted by Bob K4TAX

While the inverters I have both have internal DC fuses. With a 100 amp demand and a fuse resistance of 0.005 ohms (5/1000) the voltage drop is 0.5 volts. To avoid this, internal to most inverters, they place two 50 amp fuses in parallel which cuts the voltage drop.

My concern with adding an external fuse or breaker is that it adds resistance to the circuit. In a high current environment, the small resistance adds to voltage drop.

Bob

I haven't seen a noticeable voltage drop across the factory- installed 100-amp fuse when the 1000-watt inverter was under load.
That said, I rarely use that inverter since I installed a 3000/9000 12-volt inverter.

Richard, how you doing?

[TitanMike]

Originally Posted by Bob K4TAX

While the inverters I have both have internal DC fuses. With a 100 amp demand and a fuse resistance of 0.005 ohms (5/1000) the voltage drop is 0.5 volts. To avoid this, internal to most inverters, they place two 50 amp fuses in parallel which cuts the voltage drop.



My concern with adding an external fuse or breaker is that it adds resistance to the circuit. In a high current environment, the small resistance adds to voltage drop.



Bob

A bigger source of voltage drop with Inverters is the use of legacy Lead/Acid batteries.

My LiFePo4 batteries deliver, when under 120-140 amp loads, the same voltage as a Lead Acid battery bank at rest and will do so for most of their stored capacity.

Yes, small voltage drops do add up but fuses generally aren't that large.

Sent from my SM-N950U1 using Forest River Forums mobile app

[Richard Dietzen]

Originally Posted by 18LT

I haven't seen a noticeable voltage drop across the factory- installed 100-amp fuse when the 1000-watt inverter was under load.
That said, I rarely use that inverter since I installed a 3000/9000 12-volt inverter.

Richard, how you doing?

Thanks for asking, 18LT. I’m glad you decided to stay and support the forum!
TBH, since I retired, my memory has definitely gotten fuzzy. It’s unduly hard to troubleshoot the electrical system. Good thing my dog doesn’t care.

I took a nice trip in September to Goodwood festival of speed. I chose a place to watch for excitement at the apex of tightest turn on the track and was rewarded by close encounter with an Aston Martin crash. I hit the grass to avoid paint chips and dust from the tire barrier. Driver was ok. Not quick or brave enough to get a picture until after the crash. YouTube Goodwood channel is great if you like to watch racing veteran cars 1930’s to 1968 Formula One. NASCAR is boring by comparison. The annual event has about a thousand classic cars in the venue and the parking lot. Didja know that Porsche made a small tractor after the war? Guess it was when there wasn’t more demand for Tiger engines but the People’s Car and sports versions hadn’t yet gone into mass production.

My Everchill 12V fridge is on the fritz. Got power, the fan turns on, but definitely won’t cool on shore power or battery. YouTube says it might be a fuse in back, specific to the compressor.
Inverter is no longer lighting display after more error codes, or making any 110 off battery, even with adequate 12.8-13.7V input,but has seemed fine at the dealer, not elsewhere. Toggled the breaker multiple times.
Everchill one year warranty has expired. Sigh. Could have suffered a prior voltage issue, but it didn’t happen until after the first converter and inverter debacle had been resolved. (Converter was replaced, for those late to the saga). LIPO battery is now disconnected at the tongue, because the solar panels would probably be trying to charge at temps below 0°F.
The WFCO OEM inverter does have a better 2 year warranty.

[EvilBatmanKirk]

Originally Posted by TitanMike

A bigger source of voltage drop with Inverters is the use of legacy Lead/Acid batteries.

My LiFePo4 batteries deliver, when under 120-140 amp loads, the same voltage as a Lead Acid battery bank at rest and will do so for most of their stored capacity.

Yes, small voltage drops do add up but fuses generally aren't that large.

Sent from my SM-N950U1 using Forest River Forums mobile app

Voltage drop is a valid concern. I am just a novice. I am learning. However the minimal voltage drop with one and half feet of 2 AWG cable and class T fuse between my batteries and inverter is a no issue to me when compared to numerous loops of extra wire, consistently inappropriate wire gauge used and poorly made electrical connections I continue to find as I go over my mini lite. 2 of my favorites: The 15ft of 8awg cable connecting the DC fuse box to battery power and the 20amp blade fuse on the 16? awg wire, for solar on the side, where it connected to the DC switch. LOL.

[Richard Dietzen]

Way Global honored the Everchill refrigerator warranty even though it was over 12 months. They have now been acquired by Lippert industries. Fortunately, the TECH SUPPORT employees have remained, including Chris and Kateley, who were very helpful.
I was able to check all the voltages at least twice, and with the aid of a diagnostic tutorial they sent, also one on YouTube that seem to be the compressor board. They sent one, and it was easy to replace. The refrigerator worked for 5 days, compressor was even quieter.
Now my lithium battery has 14.3 V terminals that are well connected to the 2ga cables. Nothing has changed except there is no voltage going into the trailer, and also no power at the solar charge controller. The isolation switch on the tongue was/is set to green. No amperage is going out of the positive battery terminal. I recall there might be a additional fuse on the driver side of the frame. I haven’t checked that. All the fuses and breakers in the power center are OK. It hasn’t been connected to shore power during this episode. Previously, the GFI on shore power stopped working before this particular problem started, and I will replace it. When I replace it, I will recheck on the 110 power and see if it makes any difference. Any other suggestions? I should probably post this elsewhere also.