Samsonite801
Solar Wizard
- Joined
- Oct 15, 2020
- Messages
- 2,979
Would some dear friend here please help me sanity-check a scenario for a minute? I'm not an EE, just some guy here who tries to pay attention sometimes.
So I have a neighbor I regularly do heavy equipment repair work for (on our co-op) who has a Solark 12k (installed in an off-grid situation, solar or generator power only), which is tripping when he gets too much leg imbalance. The cause is understood, we are going to work and try to get the expected loads more balanced-out naturally, by swapping wires out in the breaker box and get close to balanced (with all the expected loads) as we can first.
It has been a popular trend for my other neighbors here (also with Solark 12k's) on my co-op to add in the autotransformers onto the outputs, to provide better line balancing as well.
This neighbor in question here, would also like to add in an autotransformer to help balance loads (for the unexpected loads)... He said he already purchased one for this purpose (same like the other shareholders). I have not seen it yet and do not know the brand/model they are using at this point (it might be the popular SolarEdge model I'm thinking).
In the case of a Solark 12k, it already has a neutral output provided (native split-phase inverter), so the autotransformer is not being added to provide a neutral, only for load balancing.
So in this case, it is being wired in parallel only, using the output of the transformer (L1,L2,N simply wired in parallel), where you have only one 240v dual-pole breaker to parallel it in, or take it out of the circuit.
I am trying to imagine the behavior on what would happen in this topology if a neutral connection was lost between the main panel neutral and the autotransformer (where L1 and L2 would still be paralleled to the autotransformer).
I had thought of just playing it safe and putting in a 3-pole breaker (to have neutral going through it too) between the autotransformer and the breaker box, so the autotransformer is either all in or all out...
But part of me is thinking it does not matter at all.
If the hots trip and neutral is still connected to the autotransformer then nothing bad can happen (also seen in video below), and in the other scenario where the hots stay on but if the neutral was lost to the autotransformer, then what happens there?
Wouldn't the autotransformer simply act like a regular 240v load on the circuit, it shouldn't do anything bad? (since the Solark still provides a neutral to the panel for the appliances, it just wouldn't provide any balancing if the autotransformer neutral wasn't included)...
Just trying to wrap my head around this scenario, and make sure we don't add something in which could fail in a way that can over-volt any appliances. I've also tried read all the threads on this as well, and it seems I found a couple references saying this may not matter here, but it's hard to confirm, since there are a lack of threads discussing using an autotransformer with a split-phase inverter (only for load balancing, not to provide a neutral).
Here is a video showing an example of how these would wire in with a Solark 12k (in parallel topology, to a split-phase inverter):
Thanks, any help in confirming is appreciated...
So I have a neighbor I regularly do heavy equipment repair work for (on our co-op) who has a Solark 12k (installed in an off-grid situation, solar or generator power only), which is tripping when he gets too much leg imbalance. The cause is understood, we are going to work and try to get the expected loads more balanced-out naturally, by swapping wires out in the breaker box and get close to balanced (with all the expected loads) as we can first.
It has been a popular trend for my other neighbors here (also with Solark 12k's) on my co-op to add in the autotransformers onto the outputs, to provide better line balancing as well.
This neighbor in question here, would also like to add in an autotransformer to help balance loads (for the unexpected loads)... He said he already purchased one for this purpose (same like the other shareholders). I have not seen it yet and do not know the brand/model they are using at this point (it might be the popular SolarEdge model I'm thinking).
In the case of a Solark 12k, it already has a neutral output provided (native split-phase inverter), so the autotransformer is not being added to provide a neutral, only for load balancing.
So in this case, it is being wired in parallel only, using the output of the transformer (L1,L2,N simply wired in parallel), where you have only one 240v dual-pole breaker to parallel it in, or take it out of the circuit.
I am trying to imagine the behavior on what would happen in this topology if a neutral connection was lost between the main panel neutral and the autotransformer (where L1 and L2 would still be paralleled to the autotransformer).
I had thought of just playing it safe and putting in a 3-pole breaker (to have neutral going through it too) between the autotransformer and the breaker box, so the autotransformer is either all in or all out...
But part of me is thinking it does not matter at all.
If the hots trip and neutral is still connected to the autotransformer then nothing bad can happen (also seen in video below), and in the other scenario where the hots stay on but if the neutral was lost to the autotransformer, then what happens there?
Wouldn't the autotransformer simply act like a regular 240v load on the circuit, it shouldn't do anything bad? (since the Solark still provides a neutral to the panel for the appliances, it just wouldn't provide any balancing if the autotransformer neutral wasn't included)...
Just trying to wrap my head around this scenario, and make sure we don't add something in which could fail in a way that can over-volt any appliances. I've also tried read all the threads on this as well, and it seems I found a couple references saying this may not matter here, but it's hard to confirm, since there are a lack of threads discussing using an autotransformer with a split-phase inverter (only for load balancing, not to provide a neutral).
Here is a video showing an example of how these would wire in with a Solark 12k (in parallel topology, to a split-phase inverter):
Thanks, any help in confirming is appreciated...
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