Can you attach inverter directly to battery when regulator is also connected?

[Philosopher]

Today I setup my first solar panel. It is 12v 100w panel, -> 12v/24v mppt charge regulator --> 12v sealed lead acid battery. I connected the regulator to the battery using rounded crocodile clips (insulated handles, not sure of the exact word for this type of clip). My inverter is a cheap 300w one. It came with clips similar to the ones I connected my regulator to battery with.

My question is:

Can I connect the inverter straight to the battery? It would mean two sets of clips on each terminal. I think this is then regarded as parallel to the regulator / battery / panel?

So basically the setup would be: panel -> regulator -> battery -> inverter ... It seems right. And the research I did suggests this is right. Just not exactly sure if it is. If not, how else can I connect the inverter to the circuit? I tried the inverter today on the battery while the regulator was attached. The negative terminal sparked quite a bit at first connection, then settled. But I decided to take it off and ask on here to be sure.

Thanks in advance!!

[Sunking]

Can I connect the inverter straight to the battery?

It is the only way it can be done.

[billvon]

Can I connect the inverter straight to the battery? It would mean two sets of clips on each terminal. I think this is then regarded as parallel to the regulator / battery / panel?

The parallel connection will work - but get rid of the alligator clips and use appropriately sized hardwiring and fuses/breakers. A bunch of alligator clips is a recipe for burns/fire/battery destruction.

[Philosopher]

Thanks,

I'm still very new to this. What would you class as appropriately sized hardwiring? If you need any info to answer that question, please ask. What device should I use to connect the wires from the regulator to the battery terminals? And what, if different, should I use to connect the inverter to the battery terminals? The inverter has fuse attached to the positive wire already. Where else should I fuse? All info VERY MUCH appreciated!

Cheers!

[billvon]

Thanks,
I'm still very new to this. What would you class as appropriately sized hardwiring?

Depends on your maximum loads and the fuse you choose. NEC table 310-16 is a good guide. Link here:

https://lugsdirect.com/WireCurrentAmpacitiesNEC-Table-301-16.htm

What device should I use to connect the wires from the regulator to the battery terminals?

Depends on terminations at the battery and the terminals on the inverter. For simple systems you can mount the fuse very close to the battery; that minimizes the odds of an unprotected short some distance from the battery.

For example, if the battery will take a bolt and the regulator has a compression terminal, you'd need a wire from the battery to the fuse, then fuse to the regulator. That would be one cable with two crimp-on ring terminals and one cable with one ring terminal and one bare end. If you go this route it's important to use lugs correctly sized for the wire and rated for the current, and a crimper that is designed for the lug. In other words, in most cases you can't use the Radio Shack lugs and their "one size fits all" crimper.

And what, if different, should I use to connect the inverter to the battery terminals? The inverter has fuse attached to the positive wire already. Where else should I fuse? All info VERY MUCH appreciated!

For safety I'd use a heavy gauge wire from battery to a fuse block with a few fuses - a large one for the inverter and a small one for accessory loads/charge controller. That way the wiring for the charge controller can be smaller gauge. However if you want to wire the inverter directly that's not too bad provided 1) the wiring is short and direct between inverter and battery (to reduce odds of accidental short) 2) the wire is appropriate gauge and 3) the arcing you will see during connection won't freak you out. If you do that then a single smaller fuse will suffice.