zanydroid
Solar Wizard
Where I am this stuff is checked at plan submission time, but after that they just trust that you followed the plan.
Cost for utility transformer installation?
- Thread starter Hedges
- Start date
As I read the code, it isn't just the Polaris that counts as a busbar, it is all the "tap" wires as well; it precludes the use of the tap rule. Your inspector might have a more generous interpretation though.
Kuma
New Member
I bought a 2000 watt inverter generator when replacing 200 amp panel. It powered the 25cu ft fridge, led light, tv with dvr and computer all at the same time. I would unplug fridge and plug in the mwave to heat food. We are on a well and the 40 gal water heater was plenty for two days of showers. And the 75 gal pressure tank kept the psi. It took me 2 1/2 days to replace due to it being mounted to adobe bricks and a few other nontypical installation challenges. And that inv gen came in handy later with PGE power outages.
zanydroid
Solar Wizard
I guess replacing the MSP in place is the final boss of DIY electrical work, so maybe I'll go for it.
Ampster
Renewable Energy Hobbyist
Yes, the Zinsco was replaced by the Siemans. At the time It was difficult finding a 200 Amp surface mount solare ready panel and I paid full retail at one of the most expensive supply houses in my area who was the only one who had one in stock so it cost about $650 if I remember correctly.
I removed the guts of the Zinsco and used the weather head to run my Internet cable run which allowed me to raise it several feet because it was in danger of being hit by tall trucks when attached to the fascia board at my eaves.
Ampster
Renewable Energy Hobbyist
The hype was not from anyone trying to make a buck. I have heard it mentioned on several boards. Since I have two EVs that I sometimes charge simultaneously I thought it was a wise risk management move. I did mention it to the PGE planner in the hopes it would expedite the upgrade. I was pleased with how fast they scheduled a crew to run the new drop.
Hedges
I See Electromagnetic Fields!
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I consider each tap wire from Polaris same as a finger on busbar. They are protected by a single breaker. If you daisy chained to multiple breakers, sum should not exceed ampacity of that wire.
The Polaris has multiple taps. It carries the current to all of them.
Your interpretation would be that all wires coming from Polaris must have ampacity equal to breaker feeding it. Or sum of breakers, if one is backfed with PV.
zanydroid
Solar Wizard
705.12(A) I think is mostly readable for this
up.codes
It talks about feeders, feeder taps, and how the rules are different based on the ordering of sources/sinks on the bus. If you put the additional source on the opposite end from the utility power you get the most generous allowances.
It doesn't actually have anything to say about the rating of splices. Presumably splice devices are assumed to be able to carry the current of the largest conductors they are rated for ?
Load-Side Source Connections | UpCodes
Explore a searchable database of US construction and building code. Code regulations are consolidated by state and city for easier navigation.
up.codes
It talks about feeders, feeder taps, and how the rules are different based on the ordering of sources/sinks on the bus. If you put the additional source on the opposite end from the utility power you get the most generous allowances.
It doesn't actually have anything to say about the rating of splices. Presumably splice devices are assumed to be able to carry the current of the largest conductors they are rated for ?
I hear you, we're a 3-EV household. I've derated all chargers to max out ~15A each. All the push for "fast" charging is so unneccessary for home charging, when there's so many hours overnight. But yeah, the old Zinsco stuff is a concern. Is it true that the newer Zinsco breakers from Connecticut Electric are safe and approved ?
Ampster
Renewable Energy Hobbyist
That is why they cost so much. I bought a couple in the interim. I should sell them on eBay.
then why not just replace all breakers with these ? assuming the AL bus bars are good
zanydroid
Solar Wizard
If you think thermal magnetic breakers are expensive imagine the fancier breakers (GFCI AFCI etc)
This expensive price is also supported by the makers and sellers knowing that it's used to kick the can down the road on panel changes
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Ampster
Renewable Energy Hobbyist
I did not have that knowledge at the time. I also thought I needed a bigger panel. I was already committed two new subpanels inside that garage wall and I could easily have fed them with new breakers that are apparently much safer. I have subsequently learned that an intellegent panel like a Span and others can manage loads in such a way that my 8kW solar system would most likely not need a solar ready panel with a 225 Amp busbar.
I thought the price of the Span panel was too much but I paid an electrician $2000 and paid over $600 for a new main panel so that would have gone a long way to subsidizing a Span, or one of the other panels that can manage loads. I am sure I could have found a good spot for a new main service breaker and another one to feed to the Span plus lots of NoAlox would have reduced the risk. When I am charging two EVs I rarely exceed 70 Amps.
I hope this is a lesson for other readers who may think there is no choice.
I get your logic; the difference is the bus finger is protected as a UL assembly; you can't get a 200A breaker that connects to a single bus finger (at least outside of an I-Line panel). Please post back if you get any issues from your inspector though.
just fyi, we have been running a HPWH (GeoSpring) since 2013 and always using HP without the resistive heat-rod. In fact, I've disconnected power to the upper/lower rods completely couple years ago in order to make sure my battery setup can handle the load during outage. The compressor has spec'd LRA=19.6A and RLA=4.5A (at 240vac). The clamp meter measured ~3.5A run time and the 5kw MPP AIO has no problem starting it. It's installed in my basement, welcomed side benefits include keeping the basement drier and abundant collection of clean condensate (distilled water ?)
Successful 200A OH service upgrade and Hybrid inverter connection
I just passed my DIY 200A OH service upgrade in PGE territory. Previously I had just a meter socket and a 100A connection to my main panel which was very crowded and would prevent me from installing new appliances like induction cooktop and HPWH. I installed a new meter + panel and moved my...diysolarforum.com
there were much to learn in the early days and a lot of unknowns. My first rooftop went on in 2007 and code has evolved quite a bit.
Span has an interesting concept, but potentially unreliable with all those "features". How does it control each circuit breaker ? relays ?
Hedges
I See Electromagnetic Fields!
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Highest amperage per QO bus finger is 125A, but they also have 4-pole breaker with 2 poles on 2 fingers of each busbar for 200A. Not needed for this project. Can't use it with (unmodified) interlock because handles are in the middle, not at end pole (extension of UL listed sheet metal interlock would likely work with it.) Not that I need > 125A "generator" input.
Entire business backup
Wondering if its possible to use an Eg4 18 Kvp after the main power meter and before the panel. Reason being, my panel is not easily accessible and very old wiring / construction . Has anything like this been done before. Sorry i'm new to this.
diysolarforum.com
Also available in Homeline. I might in the future try to do "Hawaiian Tie-In" for my sister's house, which has a center-fed CSED. This 200A branch breaker has four handles ganged, should work with interlock if desired (interlock depending on main breaker type and location.)
For the QO based system on my house, I plan to initially have stub 2/0 from 200A main breaker to Polaris, feed 2 awg through polaris with one end going to 125A main breaker of a sub panel, other end going to 100A fused disconnect for PV system.
After PG&E transfers their drop from old 100A Federal panel to new meter box with 200A main breaker only, I'll replace the stub with 2/0 fed through polaris, one end to 200A main breaker, other end to 200A main breaker of a sub panel (mounted where Federal had been).
These 2/0 (may have to be 3/0) and 2 awg wires are fed from 200A breaker, but all are in metal conduit and the 2 awg are protected at far end by 125A breaker or 100A fuse.
With wire inserted through Polaris and out the other side, this only uses two holes for four connections, leave room for future circuits.
2/0 for lead-in from utility drop, and through EMT conduit to my 200A box?
NEC chart says 195A for 3 wires in conduit, 175A for 75C which terminals usually are. 175A breakers exist so not allowed to round up.
3/0 rated 225A, 200A at 75C so I should use that?
2 awg rated 130A, 115A at 75C so I can round up to 125A as planned.
From the 100A disconnect, will route out in conduit to Sunny Island (and other loads). Route back in same conduit for battery backup. Four current-carrying conductors, derate to 80% of 130A = 104A, still good for 100A breaker with feed-through from grid. Can have 2 more current-carrying conductors if desired.
The wires back through conduit will go to interlocked "generator" breakers in sub-panels. All loads can be fed from Sunny Island during power failure, for fed by grid through Sunny Island as UPS. Its relay is 56A only, can supply more current from battery or GT PV, but a significant reduction from 200A (x 80% for continuous). Normally will not backfeed 200A panel just 125A panel important loads (refrigerators, etc.) Separate PV aggregator panel will have critical loads like communications.
what is a "Hawaiian Tie-In" and CSED ?
the Polaris is a good option for my so-crowded Zinsco, to tap the N-bar to feed sub-panel(s).
Just discovered decent source with decent pricing (but w/ shipping, so bundle up): https://www.gordonelectricsupply.com/
are there other sources out there ?
Hedges
I See Electromagnetic Fields!
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CSED "Combined Service Entrance Device" - meter socket, main breaker, busbar for branch circuits.
Hawaiian Tie-In is telling the 120% rule to go to h*ll and putting in a branch breaker maybe as large as the main breaker. But no other branch breaker so no danger of overloading busbar; it is just a wire connecting the two breakers. I don't know if will fly with AHJ or not. It is basically same as "PV aggregator panel" which is allowed to exceed 120% rule because no loads, but in this case it is both PV backfeed and load in one breaker.
Adding storage to my Enphase system
Looks like you have a good plan to help the thermostat sense the actual cooling requirements! When I lived in upstate NY back in the 1970's, I put an incandescent lamp near the thermostat to reduce the heater operation cycles below what the old "mercury tube" thermostat could sense. Heating...
diysolarforum.com
Hawaiian Tie In
Has anybody heard of the term ‘Hawaiian tie in’? We are a solar company in California. We have been told that 'Hawaiian tie in' is common practice out east. With a Hawaiian tie in, we remove all load breakers and put a lug kit to feed a sub where we relocate all house loads. This makes the...
forums.mikeholt.com
I get a lot of Square-D stuff like breaker panels, switches, meter socket from Home Depot, Lowes, eBay.
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