LargeVoltage Sag , Transformer issue?

[PeSCaLo]

Hi Guys,
I have a operational issue in a beach house (used sporadicly over the weekends) where the post Transformers dont seem to have enough capacity for the two houses in the complex. Wanted to know the best way to supplement and fix the problem with AIO inverters and Batteries.

two houses, both have Split Phase 105/215 v resting with no Loads.
each have main loads:
5 A/C Split 12KBTU
1 A/C Plit 36KBTU

With Full loads it goes down to 185V . (59Amps
When adding the 3 ton Split AC, it brings the Voltage to 140V for split second then all other 1Ton Splits Disconnect from the panel.
The test was done one house at a time. both houses are connected to the same Post Transformer.
We Think the problem is the Post Transformer is 100mt from the Meter, very thinn wire, many houses connnected to it and it has not been upgraded in 40 yrs.
We dont expect the utility to fix the problem.

We are Thinking using SRNE ASF 10Kw AIO inverter with 2 48v100Ah batteries to give is 1hr at full capacity of backup.
Critical load panel and moving all 5 12KBTU A/C to them to help the grid when all loads are turn on.

Questions, which setting would be better to use UBS? SBU? will the Inverter 10ms transfer UPS be able to kick in on time to keep all loads running?

or will I have to operate in inverter mode to keep the loads off the Grid?
@robby
@sunshine_eggo
@upnorthandpersonal

 

[sunshine_eggo]

you should not have the clamp meter around wires when using the probes.

 

[time2roll]

two houses, both have Split Phase 105/215 v resting with no Loads.

The 105/215 is a perfect reason to have the power company come out and look at the situation.

 

[goldserve]

The 105/215 is a perfect reason to have the power company come out and look at the situation.

I second this. Why are you paying a power company when clearly this is out of spec. They should fix it right away if you have a smart meter, they can pull these stats and see the issue on their end.

 

[green mountain boys]

When something like this happened to me I had the power company out and they fixed it promptly.

 

[Quattrohead]

That is not a standard voltage anywhere in the world but your equipment looks American, where are you?
It also appears your L1-L2 is low so in this instance is not a dodgy neutral.

 

[PeSCaLo]

Thanks for the reply, we are in a Banana Republic, the power Company does not and will not fix anything! We are on our own. Currently we have to run the 45Kw Genset 24/7 when we are onsite.

 

[Hedges]

One option is to feed the poorly regulated AC into a "Chargeverter", which keeps your 48V battery charged. Then feed your property with an inverter.

Another is to put an inverter/charger downstream of the genset, so it recharges batteries during a limited run time, then you run silently off batteries.

I presume grid power is cheaper and less hassle than generator. People put generator power at $1/W, but that may include purchase which is already done. Still expensive for fuel and oil changes are a lot of work.

 

[PeSCaLo]

One option is to feed the poorly regulated AC into a "Chargeverter", which keeps your 48V battery charged. Then feed your property with an inverter.

Another is to put an inverter/charger downstream of the genset, so it recharges batteries during a limited run time, then you run silently off batteries.

I presume grid power is cheaper and less hassle than generator. People put generator power at $1/W, but that may include purchase which is already done. Still expensive for fuel and oil changes are a lot of work.

Yes, thats correct, currently its costing $400 the weekend to run the Genset. SHould be less than half on Grid power.

Chargeverter is a great idea, kind of double conversion?
How many would I need, 2 per house? to make 10Kw?

 

[time2roll]

I would run straight off an inverter not an AIO. Get a separate universal voltage battery charger and double convert everything. Of course a large 48v battery in the middle.

Although as long as the generator works I would be putting a letter in writing to the power company if a phone call for service has been refused. Continue to escalate in 90 days to the proper regulatory board or political office in control. Be nice. Maybe the air conditioning company or a local electrician knows someone inside. Ask a lineman if you see one out working if there is a special procedure.

 

[PeSCaLo]

I would run straight off an inverter not an AIO. Get a separate universal voltage battery charger and double convert everything. Of course a large 48v battery in the middle.

Although as long as the generator works I would be putting a letter in writing to the power company if a phone call for service has been refused. Continue to escalate in 90 days to the proper regulatory board or political office in control. Be nice. Maybe the air conditioning company knows someone inside. Ask a lineman if you see one out working if there is a special procedure.

So, going the route of Double conversion with Chargeverter.
Need help with the Math.

House draws 10Kw with all loads
2X Chargeverters will supply 10Kw to the 48v Batteries
how big of a battery 48v would I need?

 

[upnorthandpersonal]

House draws 10Kw with all loads
2X Chargeverters will supply 10Kw to the 48v Batteries
how big of a battery 48v would I need?

If your grid doesn't go down, you don't need autonomy at all, so pick a cheap lead acid battery you find locally, capacity doesn't really matter even.

How long do you pull 10kW on a daily basis? If it's only small amounts of time an you're under 5kW most of the time, you could do with one chargeverter and a battery scaled up a little to provide the 10kW peak power and energy demand. You'd need to do a power audit for this to make sure though.

 

[Hedges]

Yes, thats correct, currently its costing $400 the weekend to run the Genset. SHould be less than half on Grid power.

Chargeverter is a great idea, kind of double conversion?
How many would I need, 2 per house? to make 10Kw?

Chargeverter only need enough for average consumption.

Inverter need enough for max continuous and motor starting surge.

"Power audit", people say.

$400 for a weekend sounds insane. 45kW is huge.
Into a 48V battery, some 1000A charge at full load. Would take a pretty big battery just to load that generator to optimum.
Seems big for "10kW load". But OK to start 10kW motors.

Understand and perhaps reducing peak and total load may be very beneficial.

 

[time2roll]

I would have at least a two hour battery.

 

[Hedges]

10kW 2 hours is 20kWh
AGM, 66% DoD, would be 30kWh capacity.
Except Peukert reduces capacity at 2C, so a bit deeper than 66% but still doable, I think.
Can discharge in 2 hours, take longer to recharge.
I think that is about $10,000 for SunXtender.
For comparison to other technologies.

Server rack or PowerPro LiFePO4 batteries, think it would be in $6000 to $8000 range. Longer cycle life, which may not matter for infrequent power failures but is good if cycled daily.

However, you may want enough battery for one night. Maybe expand to that after you have PV; then you can run indefinitely with grid down.

 

[timselectric]

you should not have the clamp meter around wires when using the probes.

It actually doesn't affect anything. I use them like that all of the time. You aren't using the CT function, unless it's selected.

 

[Hedges]

How about the reverse; do the probe connections affect readings with CT (or Hall effect)?

 

[timselectric]

How about the reverse; do the probe connections affect readings with CT (or Hall effect)?

Nope

Edit: unless the leads are running through the clamp. lol

 

[Hedges]

Nah, wouldn't affect magnetic field. 60 Hz AC into whatever complex input impedance, still zero current flow.

It would affect "NCV" reading, however.

 

[PeSCaLo]

Ok, so for one house, on the Critical Panel I will have 5000 Watt loads average consumption for 10hrs for the A/C

Batteries 48v100Ah Lifepo4
One Chargeverter seems to be enough

Regarding the Chargeverter to have it always on or to have it auto-start when power is applied, what would be the correct settings?
The idea is to make the system foolproof for the wife or any other non technical user. that it "Just works"