Step Down Trafo in Off Grid System

[bendesa]

Hi All,

I’m working on a Off Grid system based on Outback for a client. This client wants to have an outlet of 230VAC and 110VAC as well.

Is it possible to install an step down transformer after the DC-AC inverter? Like the picture show?

If it is possible should I put some protection in between the stapdown transformer and the inverter? How? What?


I hope someone can help meout on this topic?



Many thx

Regards

Ben

 

[petersonra]

You can certainly do what you're proposing but it seems kind of pointless typically if you have 2:30 in a residential system it's 230/115 so you would already have 115 volts available

 

[bendesa]

Hi Bob,

You can certainly do what you're proposing but it seems kind of pointless typically if you have 2:30 in a residential system it's 230/115 so you would already have 115 volts available

Thanks for your reply. I think I have not made the situation clear enough. The client lives in totally rural area outside the USA. There is no utility available. They have electrical appliances that run on 110 VAC (USA) and also appliences that run on 230 VAC. (Bought in the country they live).

That's the reason they want two different outlets. The Outback inverter (Export type series E) only has one outlet 230 VAC.

So I don't understand your argument. Can be my lack of knowledge but please help me out

Thx in advance.

Kind regards

 

[synchro]

Since both the 230V and 115V circuits would have a grounded conductor (neutral), I think an autotransformer in a "buck" configuration would have advantages compared to a transformer with isolated primary and secondary windings (i.e., a separately derived system). The autotransformer could have about half the kVA rating and half the inrush and excitation currents of an isolation transformer for a given 115V load.

 

[petersonra]

Since both the 230V and 115V circuits would have a grounded conductor (neutral), I think an autotransformer in a "buck" configuration would have advantages compared to a transformer with isolated primary and secondary windings (i.e., a separately derived system). The autotransformer could have about half the kVA rating and half the inrush and excitation currents of an isolation transformer for a given 115V load.

That should work as long as the 115 V equipment does not care it is being fed 50 Hz.

 

[synchro]

That should work as long as the 115 V equipment does not care it is being fed 50 Hz.

It looks like the inverter can be set to operate at 50 Hz or 60 Hz, but it's obviously only one or the other. The OP may need to consider having two different inverters if all the appliances can't use the same frequency.