Load sharing device
masincalgary
| Posted in Expert Exchange Q&A on
Long time since I’ve been here, as I achieved net zero in Calgary, Ab a few years ago via retrofitting! I need some work on my electric panel, and my installer says that he has trouble finding an electrician who is truly familiar with how to wire what we call a load meiser.
Therefore, my questions are, what do I need to know to hire an electrician for this job? What are the key questions to ask, and what are the key points and skills for the electrician to assure a good job?
Hoping for a reply soon! Thank you, Mary Anne
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Replies
"what we call a load meiser."
Do you have a link to this devices manufacture website?
To my ear it sounds like someone baffled you with bull stuffings and no one wants to install it and take the blame when this magical device fails to perform the impossible miracles you were promised.
Walta
Walta,
"A Load Miser (also known as an energy divider controller or load-shedding device) manages electrical power by automatically balancing heavy loads so your home does not exceed its electrical panel capacity. "
https://www.acdandy.com/bulletins/load-miser-energy-divider-controller
My mistake! Who I called the 'installer' was not actually the installer of my already installed load sharing device. It was the ASHP installer who was chagrined to see that it was tied to my stove, and that it caused my ASHP to stop working on a cold day. Other than that one time, it's been allowing me to live in a comfortable home with positive payback on my utilities (75% on the solar panel investment in its first year in fact).
I'm surprised to find the load miser still tied to my stove as I thought we switched it to my hot water tank (also a heat pump and very efficient).
Load shed devices like this are most commonly used with generator installations. I suggest you find an electrician familiar with generators, those contractors will be most likely to also be familiar with the device you're trying to install.
Bill
What exactly are you hoping to achieve by installing one? What is your goal?
Firstly, thank you all so much for your replies. That pdf posted by Malcolm (are you Canadian?) is the very one I have except mine is model DLM-4! It is installed and in use since about 2021. I'm looking more for repair than install (but want a well-informed repair). A couple winters ago, I made a call to the heat pump installer because my heat was off. He was chagrined to find that the load miser was linked to the stove and outdoor airsource heat pump; therefore the heat pump had cut out on a super cold day. He recommended the hot water heat pump be linked instead (it wouldn't be missed like the stove).
While having recent trouble with the stove (the stove would not turn off), I discovered that the breaker for the stove is the same for the load miser (stove wasn't labeled on the breaker panel). Also, overall, the panel is poorly labelled in that labels don't meaningfully identify the house areas. Since I lost my dishwasher due to a mis-labeled breaker, I don't want a repeat of that error. I want my breaker panel to be properly wired and labelled before I get any kind of electrical service or new appliance.
I'm surprised that I've had no issues since the last time my furnace cut out (maybe two-three years ago).
Yesterday my contractor assured me that his electrician is well familiar with load misers. I now plan to call the electric company that installed my panel and load miser and ask them to check their records--it's possible that the hot water tank was never linked.
Note 1: I am just an ordinary person, working in healthcare. I chose to learn about what was needed to get my home to net zero because at the time (2009 - 2017) few were doing it in Calgary, and I was regularly told it was impossible, including by HVAC companies who now install heat pumps. I used Green Building Advisor a lot. Asking questions about how something works really helps prepare me with decisions and who to work with (and helped me not give up).
Note 2: More helpful labelling for me will be numbering the breakers and posting a key with sufficient detail. I will do as much as I can to remove the guesswork. I'm sorry I didn't work with the electrician to do this so that the labels would be clear to me.
Thank you all for your time.
Let me first say that I am not an electrician, so may have inadequate knowledge to be helpful.
My first question is why was a "load miser" installed to begin with? Was it cost prohibitive to have the service amps installed that your home needs to handle all the electrical loads simultaneously? Or, was there some other determining factor?
What is the capacity of your existing electrical panel?
Have you asked an electrical contractor what the cost would be to remove the load miser and provide the total electrical capacity needed?
Sounds like you have an electric cooktop/oven (is it induction cooktop or "traditional"?), heat pump, and electric hot water heater. A refrigerator can also pull a significant peak load, as can other devices for short times, such as a laser printer, a bidet toilet seat, and electric wall heaters -- for example in bathrooms or garages.
If you can provide more background/details, the community here might be able to provide better advice.
Thank you! I have a load miser because my 1969 home is 100 amp service and better would be 200 amps (for solar plus heat pumps). But in this neighbourhood the electric lines are buried and yes, it would have been cost prohibitive to dig and add more amps. In fact, I was stuck on that until I learned of load sharing devices through an article here (maybe there was a link to the grants in Maine or Vermont).
I spent most of this day trying to better label my panel. In some cases, there are several breakers to the same lights and outlets. Seems a bit wasteful to use breaker capacity that way. It'll be interesting to hear what my nephew, the electrical apprentice, has to say about the detail I have compared to the labels on the breakers. (Maybe electricians don't need the full detail?).
My hot water tank is a heat pump (very efficient), well sized and insulated so it doesn't come on much. My contractor says it is the most efficient appliance in his home, and he has more appliances than I. My stove is electric (20 yrs old), and when the time comes, its replacement will be induction.
I haven't used my dishwasher since it blew out on account of a breaker mislabel, discovered when the hot water tank heat pump was installed. Of course I want the capacity to replace it, and the panel will accommodate it.
I also don't use a dryer, but again, the panel will accommodate an electric dryer (it has a dedicated breaker) if I get one.
Gas has been disconnected since 2019 or so. I had the gas meter also removed.
Our weather has been mild, and the problems I'm having with my stove and kitchen overhead light popping and flipping the breaker--I suspect are unrelated to each other, and simply indicating repair needs.
I want my panel to be in order before any further repairs.
I suspect that because I was among the first to have a load miser, that we didn't realize that pairing the hot water tank with the heat pump was much better than pairing it with the stove. I'm surprised that hasn't been fixed since our discovery of the issue (furnace/heat pump was knocked out by the stove one winter) and I don't know who dropped the ball, but it's time I knew more about what needs to be done (such prioritize the furnace- which will be the air handler in resistance mode- and drop the hot water tank heat pump during those hours or few days), and make sure that the electrician knows how to do that.
The pdf that Malcolm posted is easy enough to read and makes me think that it's not as difficult for an electrician as I had imagined (given how chagrined my furnace/heat pump installer was to find out that the stove had knocked out my furnace on a real cold day).
I'm grateful for all information given by readers to me.
I'm not so sure you need a load miser here. Heat pump water heaters don't draw all that much electricity, certainly no where near what an electric resistance water heater would. You might very well be fine without it, even with 100A service. If you did have an issue, I would probably set the stove up to be the load that is dropped.
The "heat pump" I assume is a multisplit? Maybe a central unit? I'm not quite clear on that. Regardless of what type it is, the indoor and outdoor units are part of the same system, and need to be treated as such. That means you CANNOT drop out one side and not the other. The indoor units CANNOT work without the outdoor unit. If you have to set any of that to drop out, it is an all or nothing deal. I would not set this as the interruptible load at all, not any part of the system.
If you have stages, I would set the water heater to drop out first, since it will be least noticeable by you. The tank will hold a reserve of hot water, so you can continue to get hot water even if the unit isn't powered, although it will run out over time. I'd set the stove as the next thing to drop out, since it's less important than your heating system, but also more disruptive to your home if it's disconnected by the load miser.
Do you have a list of your large electrical loads? If all you have that are "large" are the stove, heat pump system, and heat pump water heater, that's not really all that much. The stove may have a 40A or 50A breaker, but it probably averages less than half of that while you're using it, probably even less usually. A typical range is 4 burners and an oven, and that breaker can run *all* of that at the same time. Running only one burner is likely running around 6A, maybe 10A for a "big" burner. A heat pump water heater is probably a 120V circuit, maybe 10A, but only on one leg of your service. That is a bit more complex to explain, but it isn't a "big" load. The heat pump is probably something under 30A, and likely uses less than that most of the time.
There is a little thing in the electrical world we call "the 80% rule". It means you're not supposed to load up a circuit to more than 80% of rated capacity for "continuous" loads, which are defined as loads that are on for more than 3 hours at a time. That means all your normal stuff probably won't use more than 80% of the breaker rating ever, especially the heat pump, so it's really a 24A max load. You can actually use ALL of your 100A service, as long as it's not for more than 3 hours, and those loads are likely to cycle within that time, so you won't be running all out the entire 3 hour window. Think about it: you probably finished boiling that pot of water before 3 hours, the pie in the oven is done. The water heater maybe ran once in that time. The heat pump might have been running the entire time on a very hot day, but nothing else was.
So be careful about going overly conservative with a load management system that disconnects loads -- you might not need it to be so aggressive.
One other thing: electricians don't generally do repairs on equipment. Electricians install equipment, and replace things that go bad. As an example, if a light switch fails, your electrician is going to replace it, not try to take it apart and fix the internal contacts. The same goes for those load misers -- it's unlikely an electrician is going to be able to replace one that has failed. The electrician may need to replace the entire unit.
I recommend you also ask your electrician to check the electrical load of your entire home with things running. This is very easy to do using what is known as a "clamp meter", which is an amp meter that can be temporarily clamped around a wire to measure current. This needs to be done in AT LEAST TWO PLACES (both service entrance "hot" conductors, which are typically either black or red wires in the main panel). See what the *actual* load is to determine if you really need to disconnect anything.
Bill
Bill,
If you agree, I think you might jump back in here to provide some "stern" advice, along the lines you mention to check the loads at each circuit, but in even more detail than that, because I suspect there is some critical miswiring in this home that could prove to be a life-safety issue.
Why do I suspect this? Because @masincalgary says "In some cases, there are several breakers to the same lights and outlets." which should NEVER be the case.
I don't know the regulatory environment there, but here in Washington state, electrical "technicians" are supposed to be supervised by a "licensed electrician" but are often sent out on calls with no supervision.
I am concerned about all the people involved between the homeowner and the problem. A "contractor" and an "electrical apprentice" nephew. No offense to these people, but there needs to be high confidence that a fully qualified electrician is doing the work, and has discussed the problem directly, and the only way to do that in my opinion is to work directly with the licensed electrician.
The sooner, the better.
Something is off on your setup, lights should not pop breakers. Usual culprit is bad connection in a junction box or screw through a wire in the wall.
As for load reduction, I have an all electric home as well. Just looked through the past month and my peak was 12.5kW so 50A. Not very cold yet, so that would add a bit more, but would still be bellow 100A. You should never have to dump loads.
About the only things I would add to load dump is the stove and water heater. Usually these load dumps are more needed for EV chargers.
I really appreciate these replies! The reason for the load miser is that I could not get a permit for a solar system without a 200 amp service, and the load miser enabled the permit. It was explained to me that functionally, I am unlikely to need the load miser because no one has all their electric load on at the same time, but to meet code, I needed to accommodate for my 100 not 200 amp service.
That explains why I've not noticed a problem before. (Low load).
But the time that my furnace/heat pump would not turn on bc of the load miser signals a definite problem. The electrician should have thought it through. Heat is critical in Canada. (No a/c needed here). And it appears that problem was not rectified bc my stove is still tied to the load miser and the hot water tank is not.
If someone installs a dishwasher or fixes a light switch, they might turn the breaker off and on. I want those to be labelled correctly. I also want to know what's going on if a breaker flips. I don't want to be staring at a big mystery when it's so important to my home.
My nephew is helping me understand because as you see, I ask a lot of questions. I'll get his thoughts on it, or that he doesn't know. He's new to this, and not inclined to overstep. For sure it was super time consuming for me to check the breakers and I've more to do. He's already alerted me to the solar breaker and not to touch it (It has a clear red label).
Once I've done all this, then I'm going to have a licensed electrician in here to get it set --I'm just basically making sure I know enough to ask the right questions and be more knowledgeable. I'm responsible in the end. "Buyer beware" was drilled into me in my business law class. We can have the greatest people working for us, and still mistakes happen. If we aren't even alert to the signs we're not in a good position.
Thank you for all your suggestions. I'll now add the size of breakers to my panel key. My panel replaced an old one. The old one was the one that blew out my dishwasher bc it was poorly labelled. I'll bet when they replaced the panel, that they did not "start over" and check where the breakers were servicing. The whole thing was very time consuming because of the size of entrance from the city, and the difficulty - if you can believe it - of keeping my land line intact (which I insisted upon).
I like the idea of the amp meter.
This whole effort here of mine is to make sure that I have the right fully qualified electrician. I don't feel comfortable when someone like my heat pump installer is not impressed with the work when called out, and when he still tells me that he's having trouble finding an electrician!
More to come I'm sure.
You mentioned labels several times. All breakers must be properly labeled in compliance with electrical code, not to mention part of "good workman like manner". I suspect the last work you had done was very bad to begin with. And going back to the earliest comments, that probably has a lot to do with the reluctance of electricians to take the job - no one enjoys cleaning up other electrician's messes, and assuming responsibility going forward.
It's pretty common for labeling to be a bit less than you might like, especially since it's very common for circuits to be shared between several things (plugs in two rooms, etc.). Do a few renovations, decide to call a room something else, before you know it, the labels aren't very helpful. Reality is that the labels get abbreviated, and sometimes the electrician doesn't know what to call something so they make up a name. Other times, a homeowner will label it "Bob's bedroom" or some such, and a future owner won't know who Bob was, so the label doesn't have any meaning anymore. This is an issue, but doesn't necassarily mean you had a bad contractor.
If several breakers turn the SAME THINGS on and off, that is likely a BIG issue -- it implies you may have several circuits tied together somewhere downstream, which is a BIG problem. That is something you absolutely want to have checked and corrected. Someone will have to disconnect ALL the circuits in the panel and go through them all with a continuity checker. Expect an open ended "time and materials" kind of job for this, because it tends to burn through a lot of time for a crew, and they have no way to know how much ahead of time, since they don't have any idea what problems they might find -- or how difficult it will be to get to them to correct them. BE SURE to mention this issue to your crew! You NEED to get this checked out!
Panels shouldn't "blow out" anything. Miswiring can damage things, panels themselves don't really do much. If this was my project, I would start by isolating ALL the circuits (turning them all off, basically), and probing everything from the panel to see if anything was tied together downstream. Depending on what I found or saw, I might lift (disconnect) all the neutrals and grounds in the panel and check all of those too. If you had some less than competant electrician (I usually think of that as DIY special sort of stuff), then it's entirely possible you have un related circuits connected together in some random junction box somewhere, and that is a big problem -- and something that can be very tedious to find! The actual repair tends to be pretty easy, FINDING the problem is the hard part!
Once the wiring is all cleaned up so that "miswired circuits" can be ruled out, you should have an easier time getting things figured out. Normally load management isn't that big a deal -- the load miser device just watches the total current (amps) on the service, then disconnects whatever load it's set to disconnect if it sees the total electrical demand exceed some set limit. They're really not very complex devices, so the problems you're having make me think something is not right somewhere in your home, likely some kind of incorrect wiring somewhere that needs to be found and fixed.
Bill
Thank you, Bill,
I am feeling much better, although there are still a few things for me to get confident in before hiring to rewire/correct the load miser's connections.
My nephew helped me check all the breakers. He also explain how the labelling could be so poor. (Naming things by old names no longer meaningful like "kitchen nook" and labelling something that would keep an electrician safe for a breaker that he didn't know exactly what it connected to--like "lights and plugs" for a single plug, and having several bearing the same name "main floor lights.") And some important labels are missing (stove and ASHP). Maybe that's all OK for most people, but not for me. Now I've a detailed key to all the breakers.
My father bought this house from the builder, two yrs after it was built, so I don't know if the builder was a DIY kind of man or not. No one since then has been DIY. In fact my father's degree was electrical engineering, but he'd be the first to admit he could not replace an electrician.
Because I left off the breaker connected to the light switch that popped and sparked, there were times I confused what was disconnected via that breaker with other breakers, which is why I thought there were duplicates. (When I turned other breakers off, sometimes I forgot that the reason something wasn't working was bc it was connected to the breaker that I was keeping off). It's definitely easier with two people to check everything. Now nothing looks duplicate and I'm glad to know that duplication would indicate a BIG problem.
I can now see that I actually have considerable extra room. For e.g. some breakers have very little on them, such as one outlet, and another with just the doorbell. One has nothing! (We turned everything on and nothing went off when we flipped that breaker off). By the way, I don't have a multi-split system. My heat pump uses existing ducts throughout the house. The air handler is on a 15 amp breaker. The ASHP is 35, and the Load Miser is 50, and I don't have a breaker dedicated to the stove (it's hooked into the Load Miser breaker).
The breaker for the clothes dryer is the same size as my hot water heat pump (30 each) but I don't own a dryer (high altitude dries hanging clothes very fast). This helps me with considerations for how to re-wire the load miser. And I see a potential problem if both the stove and Load Miser need separate 50 amp breakers if separated.
Thinking outloud: Maybe the stove should be on the 50 am breaker occupied by the load miser, and then the load miser could share the dryer and the hot water tank. If the resistive back up heater drew too much energy, the dryer could be shut off, and if it needed still more, then the hot water tank. Maybe that would work. I might call Dandy tomorrow (load miser producer) to ask. If the load miser can't share with two breakers that sum > 50, then maybe it could share with the dryer and a the breaker with the empty plug, of the single plug . Three of those are all even beside each other on the panel. Dandy must have some answers for various sizing situations.
Question especially to you Bill: What could the installer of my hot water tank have meant when he said he was sorry I lost my dishwasher bc it got fried due to a mis-labeled breaker? I thought he was saying that it wasn't labelled, and therefore a surge of electricity fried the computer part of the dishwasher, and it was irreparable. That alert me to the cost of a panel labelling mistakes! I'm trying to square this with what you said about mis-wiring be the issue rather than the panel. We couldn't check the dishwasher outlet because it is built into the cupboard and it's too hard to pull out.
Also if anyone in this conversation has a load miser, have they noticed a hum? At one point during my checking of breakers unrelated to the load miser breaker, the hum got very loud so I switched it off (flipped the breaker). Within minutes I flipped it back on, and the hum is now very low.
Lastly, the pop was my dimmer switch. Inside, the wiring is correct. One small issue resolved.
EEs and electricians aren't the same thing, that's true, but many have done both (like me :-). I still work in the field with my crews sometimes, which earns a lot of respect from the contractors when they know the guy that did the design can also actually do the installation work too!
You would not typically "share" a breaker with that load miser device. If it's the way I think it is (I haven't worked with your specific model before, but I have worked with similar units from other manufacturers), it works "in line" with the device it's controlling, which means there is a breaker in the panel feeding the load miser and then the load miser feeds a controlled device (stove, etc.). This lets the load miser interrupt power to the controlled device when needed.
When working out loads, it is the actual demand/load that matters, not so much the ratings on the breakers. Adding breakers to a panel does NOT increase the load on the service, adding equipment (motors, lights, heaters, etc.) does. You won't overload anything by putting a few more breakers in the panel if you want to split things up a little more. Also, typical residential service is 120/240 single phase, so there are two "legs" or "hots". You will have single pole breakers (one slot, one handle), and double pole breakers (two slots, often two handles with a tiebar between them). Loads fed by single pole breakers will load up ONLY ONE of the two legs of the service, but loads fed by double pole breakers will typically add an equal load to BOTH legs simultaneously. That means You could have a double pole breaker with a 32A load on it (which might mean a 40A or 50A breaker), a single pole breaker with 8A of load, and another single pole breaker with 12 amps of load.
This is where you can potentially run into issues if you're pushing the limits of something: if those two single pole breakers are next to each other on the same side of the panel, they should be on opposite legs of that service. That means one leg will "see" 32A (load from the double pole breaker) plus the 8A load of the first single pole breaker, for 40A total load on that let. The other leg will see that 32A from the double pole breaker again, plus the 12A from the other single pole breaker, for a total of 44A on that leg. That's not a particularly big imbalance, and not a problem. The 4A of "imbalance current" will flow on the neutral conductor of your service. Now let's say the two single pole breakers are on the SAME leg of the service. You now have one leg with only the 32A from the double pole breaker, but the other leg sees that 32A from the double pole breaker plus the 8A from the first single pole breaker plus the 12A from the second single pole breaker. You now have 32A on one leg of the service, and 52A on the other leg -- a much larger imbalance! It's entirely possible to overload only one of the two legs if you have a severe imbalance among your loads, so that's another thing for you to check. If you need to rebalance things, all you need to do is move some of the breakers around in the panel to better split the load between the two legs of the service. That clamp-on ammeter check I mentioned earlier is needed to check for this.
The hum may be a sign of an internal problem, or it may just be a transformer mounted on a piece of sheet metal. There is a nifty process in physics known as "magnetostriction", which is the property of some materials -- including the steel used in the lamintations of the transformer -- to change dimensions slightly in the presence of magnetic fields. That's where the hum comes from with transformers. Really loud hum can sometimes mean loose laminations (the laminations are the steel pieces that are all sandwiched together in the middle of the transformer), it can sometimes mean the transformer is mounted on an open piece of sheet metal where you get resonance amplifying the sound, but it can also mean there is a fault like a short circuit somewhere overloading things. If it's a fault, the unit is likely to not only be noisy, but to also get pretty hot. That's another thing to check for. Note that loose screws can sometimes make things noisier than they should be, so it's entirely possible the noise doesn't actually indicate a problem.
Regarding the dishwasher getting "blown out", I'm not sure what that could have been. Using a too-large breaker on the dishwasher could have let something internal to the dishwasher fail before the breaker tripped, but a failure like that would still have originated with an internal fault with the dishwasher. A too small breaker would just cause nuisance trips, which are annoying, but probably wouldn't have damaged anything. If the unit was miswired so that it got 240V (running line to line, hot to hot) instead of 120V (running line to neutral), THAT would have blown up your dishwasher, but it would be due to an incorrect installation. Problems due to internal issues within the dishwasher are things for the manufacturer's warranty to deal with. Problems due a faulty installation are things for the installation contractor's liability insurance to deal with.
Note that if you get "surges" or other transients on your utility feed, I strongly recommend you add a small TVSS (Transient Voltage Surge Suppressor -- the fancy trade name for these devices) to your main panel. These are basically whole-home surge protectors. They are great insurance against problems, and they aren't very expensive to buy or to install. I hightly recommend everyone use one, and many current codes require them. I personally like the little units made by Ditek for this application, but there are other manufacturers.
Bill
Bill --
Re: the dishwasher getting "blown out," a big current imbalance can cause the voltage on the overloaded leg to drop, which causes the voltage on the underloaded leg to rise. Back in the days when incandescent bulbs were a thing I remember seeing a short on one leg burn out the bulbs on the other.
True, but that would also likely damage other things. A "big imbalance" alone won't do it -- i.e. 100A on one leg and 1A on the other isn't going to get the voltages so messed up that things get damaged. What WOULD cause an issue like that is a bad neutral connection somewhere, which can happen, but is pretty rare. It's worth the OP checking with her electricians to check that anyway.
Bill
We've been seeing load-balancing SPAN panels on a lot of our all-electic home designs, which are often right at the edge of where 200A is enough. Things like multiple ducted heat pump heaters, a well pump, sewer ejector pump and one or two electric car chargers, often with PV panels and a propane-fired generator, are easier to handle with dynamic load balancing. Sometimes we still have to bump up to 400A but that's a big expense and the exterior equipment is all larger than we're used to seeing on homes, so there's incentive to stick with 200A service.
I think my overall load and usages are really low. Some day, I may go back over my bills to see the highest usage in a month. What a great idea. Not today, however!
(I don't use a dishwasher, a dryer, a garburator, no hot tub, sauna, water pump, etc. Just solar ASHP and air handler, both the smallest fit for 1800 sq ft home).
Your electric bill shows what amount to very slow averages of load. You need to know your peak loads over much shorter time periods. You CANNOT use an electric bill to see if you are maxxing out your service for brief periods, although you usually CAN get a pretty good idea of your average load levels.
The biggest thing anyone is likely to have that would be loading the system is an EV charger. Those are BIG loads, and they are long term (typically hours). Any large electric resistance heating device (aux heat on a heat pump comes to mind) is another thing to think about, and if you have an electric resistance clothes dryer.
Dishwashers, garbage disposals, and sump pumps are all relatively small loads -- typically 120V devices at around a kw or less (~8-10 amps or so at most, maybe 12ish if you have a really beefy sump pump).
Bill
Re the hum: Spoke with Dandy, the manufacturer and a fellow there said the hum is the connector. Not unusual and not indicative of a problem. He usually suggests flipping the breaker off and back on, (which is what I did, and it worked). If that doesn't reduce the hum, then he sends someone out.
A connector making noise would make me suspicious. If it's vibrating a bit in it's mounting hole, a pit of EPDM stuffed along side it between the chassis and the connector will likely quiet it down. I would check if it's noticeable warm though. Hot electrical things are usually indicative of a problem, and with a connector, that "problem" is likely to be high contact resistance which is something you'd want to address.
Bill
What is the point of not upgrading the service to fully meet your current demands. Given that the average customer usage grows every year you are only wasting money on equipment that is irritating to use and delaying the inevitable.
Sometimes service upgrades are prohibitively expensive. Also, while 100A service can be a bit light these days for certain peak times, 200A service is only very rarely ever an issue. Average load on a typical residential home is about 1.5kw, which is about 6.25A.
As an example for those who think you need massive services: Imagine you need 201 amps, all the time, for your electricity guzzling home. What is that going to cost you? Let's assume 15 cents per kilowatt hour. With 240v service, and assuming ~90% power factor (I usually see around 92% at work, but we'll assume a bit worse here, since it actually makes the costs LOWER in this case), that means you are using 201A * 240V * 0.9PF = 43.4kwh EVERY HOUR of the day. Multiple that by 24 hours, you are at 1,042kwh in a day. 30 days in a month brings us to 31,260kwh per month (note I carried a bit more decimal precision through there if you see some differences in rounding). That's $ 4,689/month in electric usage with 15 cent per kwh power. I doubt anyone has seen anywhere near that high a bill at home.
If you have a $200/month bill at that same per-kwh rate, your average load is 1.85kw, which works out to about 8.57A using the same math I used above, but worked "backwards".
Outside of relatively short-duration load peaks, very few people are going to have a problem with the standard size residential electric services.
Bill