Just blew both 200a Class T fuses after precharging with a 25w / 30ohm resistor…?

[ArtieKendall]

@Will Prowse continuing our discussion from the other day, a fine example.

Here’s a better way to precharge that will give you a very good indication of you have a short

Really helpful video. At 5:07, were the voltmeter probes just attached to the inverter's battery inputs?

 

[justgary]

Really helpful video. At 5:07, were the voltmeter probes just attached to the inverter's battery inputs?

Yes.

 

[rhino]

@dhy4buva did you get this resolved?

 

[dhy4buva]

@dhy4buva did you get this resolved?

Yes! Thanks to everyone for the responses. It was indeed reversed battery leads that blew the fuses. Thankfully, EG4 has incorporated reverse polarity protection in the 6000ex units. We replaced the fuses, rewired the leads correctly, and both units fired right up and have performed admirably over the last three days. From small loads to larger 6kw loads, they’ve been excellent.

I’d like to add that Signature Solar was fantastic throughout the process—sympathetic to my situation, and prepared to assist in any way necessary. My future solar business will certainly remain with them.

 

[kromc5]

Yes! Thanks to everyone for the responses. It was indeed reversed battery leads that blew the fuses. Thankfully, EG4 has incorporated reverse polarity protection in the 6000ex units. We replaced the fuses, rewired the leads correctly, and both units fired right up and have performed admirably over the last three days. From small loads to larger 6kw loads, they’ve been excellent.

I’d like to add that Signature Solar was fantastic throughout the process—sympathetic to my situation, and prepared to assist in any way necessary. My future solar business will certainly remain with them.

That is a wonderful outcome and impressive that they are functioning properly.

 

[SniperX]

I found the same type of bulb Dexter used https://www.amazon.com/Forklift-Bulb-Volt-Watt-BA15d/dp/B0046IJTFE
and interestingly a socket that can easily be mounted as well: https://www.amazon.com/Bayonet-Sock..._bxgy_vft_none_img_sccl_1/132-1464949-5005210

I might actually try this setup. I have the dual bank switch as well since I was going to mount a resistor to the switch but this is much better idea as others have also mentioned above to use a bulb but was more convincing seeing a video of it in action

Did you do this? If so, do you have a picture? Thanks for the links.

 

[rhino]

Did you do this? If so, do you have a picture? Thanks for the links.

Actually I did and was getting ready to take picture and/or video this evening. It seems to work well.

 

[SniperX]

Actually I did and was getting ready to take picture and/or video this evening. It seems to work well.

I have both in my cart waiting on your answer. Thanks!!! Hope to see that pic. Appreciate the quick response.

 

[hwy17]

A regular 60w bulb will visibly light up on 48v too.

 

[justgary]

A regular 60w bulb will visibly light up on 48v too.

As will a regular 100w bulb. I just recommissioned my 48V Magnum MS4448PAE inverter a few weeks ago using one.

 

[efficientPV]

I was just doing a test yesterday of a 100W 120V lamp on 60V and it drew a half amp. A friend of mine who worked at lamp division would go nuts every time someone called it a light bulb.

 

[ArtieKendall]

Question: I've only seen the pre-charge issue discussed with batteries. Is there also an issue with solar or AC input being connected to a unit with depleted capacitors?

 

[rhino]

I have both in my cart waiting on your answer. Thanks!!! Hope to see that pic. Appreciate the quick response.

This is my "temporary" solution since I'd prefer some kind of push button and not some rotary switch. You can see the bulb next to switch in upper left corner. Since this switch has two position I have it so that first position pre-charges the first Quattro and 2nd position pre-charges 2nd Quattro.

Each red wire connects to a Quattro. They both have fuses near where they connect to the Quattros since that wire will be powered whenever the inverters are on.

The white wire is built-into the bulb socket and connects to a battery busbar (it's red again on the busbar you see since I had to butt splice more wire onto it to reach and used red). It also has a fuse on it since that will be powered whenever busbar is energized.

So there is total of 3 fuses. I've tried it once already and works like Dexter shows on his video.

 

[Hedges]

Question: I've only seen the pre-charge issue discussed with batteries. Is there also an issue with solar or AC input being connected to a unit with depleted capacitors?

Nope.
PV array is a moderate current source. No risk of it delivering 1000's of amps momentarily.

On the other hand, if you have a rats nest of cables with MC connectors between multiple arrays and multiple inverters, it is possible to connect the 480V charged bank of capacitors in one inverter reverse-polarity to the protection diode of another inverter. Don't ask me how I know.

If I feed AC, rectified (and transformer isolated) to the PV input of an inverter as I'm considering, in that case I will want to precharge.

 

[SniperX]

This is my "temporary" solution since I'd prefer some kind of push button and not some rotary switch. You can see the bulb next to switch in upper left corner. Since this switch has two position I have it so that first position pre-charges the first Quattro and 2nd position pre-charges 2nd Quattro.

Each red wire connects to a Quattro. They both have fuses near where they connect to the Quattros since that wire will be powered whenever the inverters are on.

The white wire is built-into the bulb socket and connects to a battery busbar (it's red again on the busbar you see since I had to butt splice more wire onto it to reach and used red). It also has a fuse on it since that will be powered whenever busbar is energized.

So there is total of 3 fuses. I've tried it once already and works like Dexter shows on his video.

View attachment 161960

Is this something you would use? Came from a suggestion on another video. https://www.amazon.com/dp/B07FB2382G?ref=ppx_pop_mob_ap_share&th=1

 

[SniperX]

This is my "temporary" solution since I'd prefer some kind of push button and not some rotary switch. You can see the bulb next to switch in upper left corner. Since this switch has two position I have it so that first position pre-charges the first Quattro and 2nd position pre-charges 2nd Quattro.

Each red wire connects to a Quattro. They both have fuses near where they connect to the Quattros since that wire will be powered whenever the inverters are on.

The white wire is built-into the bulb socket and connects to a battery busbar (it's red again on the busbar you see since I had to butt splice more wire onto it to reach and used red). It also has a fuse on it since that will be powered whenever busbar is energized.

So there is total of 3 fuses. I've tried it once already and works like Dexter shows on his video.

View attachment 161960

This is the video. Start at 6:29 seconds where he describes his.

 

[rhino]

Is this something you would use? Came from a suggestion on another video. https://www.amazon.com/dp/B07FB2382G?ref=ppx_pop_mob_ap_share&th=1

I'm weary of something that doesn't have a DC rating.

This is the video. Start at 6:29 seconds where he describes his.

Is there info on exactly what he used?

 

[Hedges]

I'm weary of something that doesn't have a DC rating.

If low current limited by resistor, shouldn't be much of a problem.

Many switches also have DC rating, but usually something like 28VDC.

It is true, though, that AC switches can have some pretty narrow contact gaps.
Maybe a long-travel plunger switch would be better. Depending on how built inside.

 

[hwy17]

https://www.mouser.com/c/electromechanical/switches/pushbutton-switches/?voltage%20rating%20dc=60%20VDC

 

[rhino]

Based on what @hwy17 posted looked on digikey as well since they are close by and saw this one which is rated for 3A at 240V DC: https://www.digikey.com/en/products/detail/eao/82-5151-1000/8736324