Hedges
I See Electromagnetic Fields!
- Joined
- Mar 28, 2020
- Messages
- 20,497
I don't know much about it, but I am under the impression I will need an auto transformer and that is part of the order I"ll be placing today.
Personal opinion, but "I don't know much about it" should not ever be in the same sentence with "is part of the order I'll be placing today." Best to understand it.
The multiplus puts out 230V, but does it bond one of the two wires carrying 230V to ground? If so you have a bit of a problem. The autotransformer would normally use the two wires of the 230V as two 115V legs, and the center tap of the autotransformer is the neutral. You would normally bond that neutral to ground in your 115V distribution / breaker panel. If one of the two 230V lines is already bonded to ground, you have a problem.
There are a couple other threads on using autotransformer.
Typically for Europe, 2-wire 220V has one wire for "Neutral" bonded to ground. The GroWatt, at least some models, appears to perform that bonding with a relay when grid disconnected, passes through neutral from grid where it is bonded when grid (or generator) connected. We aren't sure that the design allows "Neutral" to be safely driven to 120V if connected to US style 120/240V split-phase (even if internal bonding defeated).
If you have small 120V load, you could use an isolation transformer (not autotransformer) to take in 240V single-phase (one lead grounded), and produce 120/240V split phase. That's two poles of 120V, typical for a house. Transformer only needs to be large enough for those loads.
You could wire the auto transformer without grounding centertap. Then, it would get 240V and neutral from GroWatt, an produce with its centertap a single 120V phase.
Your heat pump likely can run on 240V single-phase, but double check.
Your generator may or may not have output floating so it could connect to 240V with one side grounded. If it does, and if it has 120V outlets on both phases, half of them would have a hot "neutral", which isn't good. If it is only hardwired output, could be OK.
Thanks!
That might take awhile. I don't have anything figured out... But from what I'm gathering the 230V supplied by the Multiplus isn't optimum. Any idea what I would need to do? Step down transformer?
Or perhaps I should go from the Multiplus II to the Quattro II since it apparently can deliver split phase 230V power?
I have no idea what split phase and three phase means. But the Quattro II apparently has "hybrid PowerAssist technology plus multiple system integration features such as three or split phase operation and parallel operation." I would assume split phase would mean I wouldn't need an auto transformer. Whether it makes it easier to split the power into the 110V (which I think it does because it's split phase) or not, I don't know.
3-phase would be three inverters, probably each producing 230V sine waves but each 120 degrees apart in phase. That's for 230V/400V "Y".
I think the Victron units do offer floating output, and Victron has an auto-transformer which will work with them.